Seminaria Instytutowe 2024/2025
Seminaria odbywają się co tydzień, w czwartki o godz. 13:00 w budynku Obserwatorium Astronomicznego UAM przy ul. Słonecznej 36. Osobą odpowiedzialną za ustalanie terminów i tematów wystąpień oraz za przebieg seminariów jest prof. UAM dr hab. Tomasz Kwiatkowski.
W celu umożliwienia osobom spoza Poznania udziału w naszych seminariach, pod wybranymi referatami udostępniać będziemy linki do sesji MS Teams. W celu przyłączenia się do nas w trybie wideo konferencji (bez logowania) należy kliknąć link w przeglądarce Google Chrome (w innych może nie zadziałać), wpisać swoje imię i nazwisko i czekać na dopuszczenie przez organizatora. Alternatywnie można użyć osobnej aplikacji MS Teams.
Seminaria odbywają się w sali wykładowej Instytutu Obserwatorium Astronomicznego, przy ul. Słonecznej 36, w czwartki o godz. 13:00.
Z dworca PKP można dojechać tramwajem (patrz: jakdojade.pl). Dla przyjeżdżających samochodem dostępny jest parking na terenie instytutu.
Zazwyczaj na referat przeznaczamy 45-60 minut, plus około 15 minut na dyskusję. Na seminaria przychodzi zwykle ok. 20-30 osób.
Do dyspozycji prelegenta jest rzutnik multimedialny (1920×1080 FullHD, format obrazu 16:9, wejście HDMI), pilot do zdalnej zmiany slajdów na USB oraz wskaźnik laserowy. Rzutnik jest standardowo podłączony do komputera stacjonarnego z systemami operacyjnymi Debian/Linux i MS Windows 11 (ten drugi z pakietem MS Office). Istnieje możliwość podłączenia zewnętrznych głośników.
Wystąpienia na seminarium są transmitowane na platformie MS Teams dla osób mających hasło dostepu. Z tego powodu preferujemy odtwarzanie prezentacji z komputera stacjonarnego. Jeśli niezbędne jest pdłączenie własnego laptopa, wówczas konieczne będzie zalogowanie się z niego do MS Teams, udostępnienie ekranu, oraz wyłączenie przekazu dźwięku (ten będzie rejestrowany mikrofonem przypiętym do ubrania). Czynności te wymagać będą dodatkowego czasu przed rozpoczęciem seminarium.
2024-12-02, RH
Wystąpienia w poprzednich latach:
2024/2025, 2023/2024, 2022/2023, 2021/2022, 2020/2021, 2019/2020, 2018/2019, 2017/2018, 2016/2017
W roku akademickim 2024/2025 wystąpili:
12 czerwca 2025
Prezentacje studenckie (IOAUAM)
misji kosmicznej do wybranego obiektu Układu Słonecznego. Koncepcje misji zostały przygotowane w ramach przedmiotu “Astronomia Układu Słonecznego” prowadzonego przez dr Justynę Gołębiewską metodą Problem-Based Learning.
Język polski, wykład osobisty
5 czerwca 2025
dr Nicolas Erasmus (SAAO, South Africa)
The South African Astronomical Observatory (SAAO) continues to play an important role in the global effort to observe and characterise near-Earth asteroids (NEAs). With an observing site located near the town of Sutherland, the SAAO hosts a range of telescopes (1–10 m class) equipped for photometry, spectroscopy, and polarimetry. The robotic 1.0-m Lesedi telescope enhances rapid-response capabilities, enabling same-night follow-up of newly discovered NEAs. SAAO has contributed to numerous international campaigns coordinated by the International Asteroid Warning Network (IAWN), including the “2012 TC” (Reddy et al. 2019), “Apophis” (Reddy et al. 2022), and “2023 DZ2” (Reddy et al. 2024) exercises. SAAO facilities were also involved in ground-based monitoring of NASA’s DART impact on Dimorphos (Fitzsimmons et al., in review). With the recent installation of one of the southern nodes of the Asteroid Terrestrial-impact Last Alert System (ATLAS; Tonry et al. 2018) and the development of the Intelligent Observatory (IO) initiative (Potter et al. 2024), SAAO is well positioned to support the increasing demand for NEA follow-up as survey discoveries accelerate.
This talk will present an overview of SAAO’s NEA-focused observing infrastructure and highlight selected results from recent campaigns. It will also outline plans to better utilise underused facilities and strengthen SAAO’s role in the international NEA characterisation community.
Język angielski, wykład zdalny
29 maja 2025
mgr Martin Solar (IOAUAM)
Supernovae are very energetic explosions as the final fate for some stars. Specifically, massive stars (> 8 Msol) are expected to end their life as core-collapse supernovae. The importance in understanding how massive stars form, evolve and explode as supernovae is because they produce heavy elements and halt the star formation in the interstellar medium, so they have a profound impact on galaxy evolution. In order to constrain the progenitor properties of supernovae, their interstellar medium environments are studied. However, the spatial resolution scale is essential for distinguishing progenitor environments directly from supernova locations. This presentation is aimed to show high-resolution observations at scales of giant molecular clouds at supernova environments. To do so, ALMA and MUSE observations are used as proxies of cold molecular gas and warm ionised gas, respectively. The multiwavelength approach gives us a complete comprehension on the conditions from which supernovae explode and understand better their progenitor properties from their molecular gas depletion time environments.
Język angielski, wykład osobisty
22 maja 2025
mgr José David Balseca Cisneros (Universidad de Alicante, Spain)
We present a study focused on the detection of large, distant objects in the Solar System, specifically those of planetary size located beyond 100 AU. This search is motivated by models of the primordial planetesimal disk, which suggest that the early Solar System may have hosted hundreds to thousands of Pluto-sized bodies, and potentially a few Mars-sized or larger objects. These predictions, consistent with both dynamical simulations and accretion models, raise the possibility that some of these distant bodies may still exist but remain undetected.
To explore this, we analyze deep-sky images collected over the past four years by the 0.68-m Schmidt telescope at Mt. Bigelow and the 1.5-m Cass telescope at Mt. Lemmon, both part of the Catalina Sky Survey. Our approach involves co-adding wide-field unfiltered images from different nights to increase the sensitivity and reveal faint, slowly moving sources. Image alignment is performed using the Tycho Tracker software, and source detection is carried out via Python codes based on the Astropy library and a matched-filter technique. This stacking method allows us to reach a limiting magnitude of V ≈ 21.5, sufficient to detect distant objects in the trans-Neptunian region. We then compare source positions across different epochs to identify candidate moving objects. For those showing consistent motion, we determine preliminary orbits using the software Find Orb, which enables orbital fitting even with sparse and low-cadence data sets. This step is essential for distinguishing real distant Solar System bodies from false positives or artifacts.
The methodology described here offers a robust and scalable framework that can be applied to other panoramic multi-epoch surveys, improving our ability to uncover faint and distant members of the Solar System population.
Język angielski, wykład osobisty
15 maja 2025
dr Priyanka Jalan (CAMK, Warszawa)
We introduce FLAME, a machine learning algorithm designed to fit Voigt profiles to HI Lyman-alpha absorption lines using deep convolutional neural networks. FLAME integrates two algorithms: the first determines the number of components required to fit absorption lines, and the second calculates the Doppler parameter b, the HI column density NHI, and the velocity separation of individual components. For the current version of FLAME, we trained it on low-redshift forests observed with the Far Ultraviolet gratings of the COS aboard the HST. Drawing on this data, we trained FLAME on ~1M simulated Voigt profiles, forward-modeled to mimic absorption lines observed with HST-COS, to classify lines as either single or double components, and then determine Voigt profile fitting parameters. FLAME shows impressive accuracy on the simulated data by identifying more than 98% (90%) of single (double) component lines. It determines b values within 15 (18) km/s and log NHI cm2 values within 0.3 (0.8) for 90% of the single (double) component lines. However, when applied to real data, FLAME’s component classification accuracy drops by ~10%. Despite this, there is a reasonable agreement between the b and NHI distributions obtained from traditional Voigt profile fitting methods and FLAME’s predictions. Our mock HST-COS data analysis, designed to emulate real data parameters, demonstrated that FLAME could achieve consistent accuracy comparable to its performance with simulated data. FLAME’s performance validates the use of machine learning for Voigt profile fitting, underscoring the significant potential of machine learning for detailed analysis of absorption lines.
Język angielski, wykład zdalny
8 maja 2025
prof. dr hab. Joanna Mikołajewska (CAMK, Warszawa)
Accreting white dwarf binaries are the most common interacting binaries in the Universe. The accretion leads to various outburst phenomena; among the most spectacular are thermonuclear nova explosions recurring with timescales from months to millions of years. The thermonuclear novae are also one of the most violent stellar explosions, contributing to galactic chemical evolution. Symbiotic novae are those with evolved giant donors. They are very suitable to study nova life cycles, because they have the higher accretion rates and shorter recurrence timescales than those with less evolved donors. I am going to present the state-of-the-art in understanding of them with emphasis on the recent results and discoveries.
Język angielski, wykład osobisty
24 kwietnia 2025
prof. dr hab. Grzegorz Pietrzyński (CAMK, Warszawa)
My main motivation is to provide detailed information about the new Polish observing facility: the Rolf Chini Cerro Murphy observatory in Chile. The observatory is located in front of the construction site of the biggest telescope in the world, the ELT and offers arguably the best observing conditions on our planet. I will present the current status of the instrumentation at the observatory together with our ambitious plans to expand its observing capabilities in the near future. Selected results obtained so far and recently started scientific projects will be discussed.
I will also present our results in the software development, instrumental projects, and first attempts in commercialisation. Finally I will mention several aspects of using the big potential of this observatory in international, interdisciplinary projects and outreach.
Język angielski, wykład osobisty
10 kwietnia 2025
prof. dr hab. Szymon Kozłowski (Obserwatorium Astronomiczne Uniwersytet Warszawski)
Oxygen is the third most common element in the Universe. It can be found virtually anywhere on Earth (air, water, rocks) and in the Solar System. Because oxygen exists in the form of three stable isotopes, their relative abundances in meteorites provide us with information on their formation locations. By studying oxygen isotope ratios you can tell if a meteorite is a piece of rock from Earth, Mars, or an asteroid. I am going to review the role of oxygen in meteoritic studies.
Język angielski, wykład osobisty
27 marca 2025
dr Krzysztof Langner (IOAUAM)
In 2022, the DART mission spacecraft impacted Dimorphos, the smaller asteroid in the Didymos-Dimorphos binary system. This system is the target of the European Space Agency Hera mission, with the Hera spacecraft scheduled to arrive in 2026 to conduct further post-impact research. The DART impact ejected a large number of rocks and boulders into the space surrounding both asteroids, some of which are re-impacting the surfaces of Didymos and Dimorphos. In this talk, I will discuss the potential effects of these boulder impacts on the surface of Didymos and their implications for the Hera mission.
Język angielski, wykład osobisty
27 luty 2025
Oleh Ryzhov (IOAUAM)
In this talk, I will briefly present the basics of how spectroscopic data can be used to identify the ionization sources in the galaxies (young stars, planetary nebulae, AGNs). This will be followed by the story of how the Extragalactic Team of Poznań applied these techniques to find out the dominant ISM removal mechanism in dusty ellipticals, selected from the Galaxy And Mass Assembly survey, which consequently resulted in the paper, published recently in Astrophysical Journal Supplement Series. Lastly, the new projects and ideas regarding the topic will be discussed.
Język angielski, wykład osobisty
23 stycznia 2025
mgr Monika Kamińska (IOAUAM)
Over the past few years the RBT (PST2) telescope of Adam Mickiewicz University, located in Winer Observatory in Arizona, has been involved in observations of Earth orbiting artificial satellites within the European sensor network of the EU Space Surveillance and Tracking Partnership (EU SST). In 2024 the network has implemented a central observation planning system (COPLA) for all optical and radar sensors in the network, which required significant adaptations of our observing system. I present the current status of the telescope, recent changes and our experience with the EU SST system.
The talk will be technical rather than scientific.
Język angielski, wykład osobisty
16 stycznia 2025
dr Michał Żejmo (Instytut Astronomii, Uniwersytet Zielonogórski)
In 2021, the Janusz Gil Institute of Astronomy, University of Zielona Gora was equipped with a system consisting of two telescopes – a main telescope of CDK design with a diameter of 20 inches and an auxiliary telescope of RASA design with a diameter of 11 inches.The two telescopes form a single system for both deep space observations and observations related to the Space Surveillance and Tracking (SST). The system was tested in Spain for a year, then transported to the hosting site in Chile.
In my presentation, I will discuss the experience of using the system, its involvement and achievements in scientific projects, its application in student education and the popularisation of astronomy, as well as future plans to expand the system with new telescopes and create a RemoteObservatory of the University of Zielona Góra.
Język angielski, wykład osobisty
9 stycznia 2025
Krótkie komunikaty naukowe (IOAUAM)
- Antoine Choukroun, prezentacja osobista, 10 min + 5 min na pytania
- Justyna Olszewska, prezentacja osobista, 10 min + 5 min na pytania
- Jakub Tokarek, prezentacja osobista, 10 min + 5 min na pytania
- Julia Pietrzak, j. polski, prezentacja osobista, 10 min + 5 min na pytania
- Jakub Tokarek, prezentacja osobista, 5 min: bieżący status teleskopów w Borówcu
19 grudnia 2024
Dominik Cieślak (University of Maryland Baltimore County)
The Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) mission provides critical insights into the exchange of carbon dioxide between the ocean and atmosphere. In addition, PACE data help clarify how airborne particles (aerosols) influence the growth of phytoplankton in surface waters. This improved understanding supports practical applications, such as pinpointing the extent and duration of harmful algal blooms—information valuable for both economic and public health considerations. Building on decades of NASA’s Earth observations, PACE promises to expand our perspective on the planet’s health, ensuring that researchers, policymakers, and communities benefit from its findings for many years to come.
Język angielski, wykład osobisty
12 grudnia 2024
dr Cyrielle Opitom (School of Physics & Astronomy, The University of Edinburgh)
Comets are pristine relics of the protoplanetary disk, where the planets formed and evolved, and preserve in their ices important clues about the early solar nebula. When a comet approaches the Sun, the ices it contains sublimate to form a huge atmosphere of gas and dust called the coma. Spectroscopy of cometary coma provides invaluable cues about solar system formation. However, comets are notoriously difficult to observe. They are extended objects, whose emission lines can be difficult to detect using ground-based instrumentation. In this seminar, I will explore how new and upcoming UV/optical spectrographs and IFUs are essential to study the composition of comets, understand their activity, and investigate the origin of species in their coma.
Język: angielski, wykład zdalny
5 grudnia 2024
Krótkie komunikaty naukowe (IOAUAM)
- Jakub Nadolny, j. angielski, prezentacja zdalna, 10 min + 5 min na pytania
- Martin Solar, j. angielski, prezentacja osobista, 10 min + 5 min na pytania
- Fabian Kaczmarek, j. angielski, prezentacja osobista, 10 min + 5 min na pytania
- Oleh Ryzhov, j. angielski, prezentacja osobista, 10 min + 5 min na pytania
28 listopada 2024
Krótkie komunikaty naukowe (IOAUAM)
- Milagros Colazo, j. angielski, prezentacja osobista, 10 min + 5 min na pytania
- Michał Michałowski, j. angielski, prezentacja osobista, 10 min + 5 min na pytania
- Sofiia Mykhailova, j. angielski, prezentacja osobista, 10 min + 5 min na pytania
- Paweł Koleńczuk, j. angielski, prezentacja osobista, 10 min + 5 min na pytania
21 listopada 2024
prof. UWr. dr hab. Arkadiusz Berlicki (Uniwersytet Wrocławski, Centre of Scientific Excellence – Solar and Stellar Activity)
Spectroscopic observations and modelling of the solar atmosphere are important tools for understanding its structure and physical processes. Solar atmosphere is an interface between solar interior and the heliosphere, including Earth and its surrounding. Therefore, detailed analysis of the atmospheric composition, magnetic structure, energy transport, heating and dynamics is necessary for proper description of interactions between the processes occurred in the solar interior with those observed in the interplanetary space and related with the Sun. All these processes are significantly stronger during maximum of solar activity. Energetic solar active phenomena, in particular flares or coronal mass ejections (CMEs) significantly increase the radiation and fluxes of energetic particles, which contribute to the so called “Space Weather”.
Analysis of the solar active events is important and require special techniques of observations and simulations. One of the method which seems to be most perspective is non-equilibrium plasma spectroscopy combined with NLTE modelling of different active phenomena. With these methods we hope to understand solar flares, prominences, Ellerman bombs, CMEs and other events as most violent eruptions potentially affecting our planet. Recently, newly obtained solar microwave data from ALMA interferometer provide a new basis for a better understanding of these events. Our research can be also extended for stellar flares commonly observed on active late-type stars where similar, or bigger, sudden eruptions can affect potential exoplanets orbiting around these stars.
Język angielski, wykład osobisty
14 listopada 2024
dr Krzysztof Kamiński, dr Justyna Gołębiewska, prof. Edwin Wnuk (IOA UAM)
Prezentujemy dwie metody przewidywania momentu wejścia sztucznego satelity w atmosferę Ziemi.
Pierwsza metoda wykorzystuje astrometrię z optycznych obserwacji obiektów na niskich orbitach okołoziemskich (LEO) zebranych w ciągu dwóch miesięcy poprzedzających przewidywany czas spadku. Obserwacje te przeprowadzono za pomocą globalnej sieci teleskopów należącej do Obserwatorium Astronomicznego UAM oraz firmy 6ROADS. Dane te pozwalają na doprecyzowanie orbity, parametrów oporu atmosferycznego oraz współczynnika balistycznego, co znacznie zwiększa dokładność określania końcowego czasu ponownego wejścia.
Druga metoda opiera się na analizie danych historycznych z katalogu orbitalnego Sił kosmicznych USA oraz danych orbitalnych uzyskanych z naszych obserwacji. Dopasowanie wyników propagacji do zaktualizowanego katalogu orbit, wzbogaconego o dane z nowych obserwacje, umożliwia precyzyjne określenie współczynnika balistycznego, co z kolei pozwala na dokładniejsze przewidywania spadku obiektu.
Język: polski, wykład osobisty
7 listopada 2024
dr Andrzej Szary (Instytut Astronomii, Uniwersytet Zielonogórski)
Over the past half-century since their discovery, pulsar studies have significantly advanced our understanding of neutron star physics, general relativity, the Galactic gravitational potential and magnetic field, the interstellar medium, celestial mechanics, and even cosmology. However, one major mystery in pulsar astronomy remains unresolved: the mechanism behind their radio emission. Although the discovery of pulsars was based on this property, there is still no consensus on the fundamental process driving it. Pulsar radio emission is characterized by highly periodic pulses, with individual pulses composed of subpulses that often exhibit systematic variations in position or intensity— a phenomenon known as drifting subpulses (Drake & Craft, 1968). In recent years, significant progress has been made in both the observational and theoretical understanding of drifting subpulses. On one hand, a physical justification for drift around the magnetic axis has been proposed (Szary et al. 2017), while on the other hand, an alternative model involving plasma drift around the rotation axis has gained traction (see, e.g., Basu et al. 2020; Basu et al. 2022). In this talk, I will present a research plan and initial results from a comprehensive investigation aimed at resolving this contradiction and uncovering the true nature of the drifting subpulse phenomenon.
Język: angielski, wykład osobisty
24 października 2024
prof. UAM dr hab. Tomasz Kwiatkowski (IOA UAM)
In recent years, the development of smart telescopes has made it easier for amateur astronomers to capture images of deep sky objects. These innovative instruments have a built-in imaging sensor and computer, which can automatically adjust their position and focus without any human intervention. They are usually controlled by a smartphone app, which can download images in real time through WiFi. In this talk, I will present the Seestar S50, a smart telescope that will soon be part of our observatory’s educational equipment. I will discuss its technical capabilities and its application in student education, assuming it is used locally, at our observatory’s park.
Język: angielski, wykład osobisty
10 października 2024
prof. UAM dr hab. Agnieszka Kryszczyńska (IOA UAM)
Język: polski, wykład osobisty
W roku akademickim 2023/2024 wystąpili:
20 czerwca 2024
Prezentacje studenckie (IOA UAM)
Język: polski, wykład osobisty
13 czerwca 2024
dr Bartosz Pieterek (Państwowy Instytut Geologiczny, Pracownia Geozagrożeń UAM)
Planetary sciences are currently one of the most developing branches of industry and science which meet humanity’s aspirations to explore Space. Just after the Moon, Mars is one of the most trailblazing research fields, as it constitutes a critical step forward in planetary exploration. Nevertheless, a detailed Martian evolution is fundamentally unknown and this carries with it significant consequences for upcoming exploration missions.
Although it is widely accepted that Mars’s evolution has been mainly controlled by magmatism expressed on the surface by volcanic centers, the ongoing acquisitions of datasets provide great advances in Martian surface visualization increasing our capability of investigating volcanic landforms that have been previously overlooked. During this contribution, the presenter will provide an integrated portrait of Amazonian-aged Martian volcanism, especially focusing on the small-scale landforms across Mars whose investigation may breakthrough our understanding of the most recent magmatic processes.
Język: angielski, wykład osobisty
06 czerwca 2024
mgr Antoine Choukroun (IOA UAM)
Determining the physical parameters of asteroids is a complex yet crucial task. Size determinations of asteroids can differ from source to source by as much as 30%. It is going to influence theoretical. studies of dynamical and thermal effects affecting asteroids. For example, it can lead to 90% uncertainty in density determinations.
In our research, we focused on studying several main-belt asteroids using high-quality data. Initially, we fitted lightcurves in the visible range using convex inversion obtaining precise information on the spin axis and an initial shape model. Subsequently, we used these results as input for another modelling technique called Convex Inversion Thermophysical Model (CITPM). CITPM optimizes the model based both on lightcurves and thermal data, providing output such as surface roughness, temperature distribution, thermal inertia, and asteroid size. Additionally, by fitting the initial models to stellar occultation observations, we determined asteroid sizes with another recognized precise method. This revealed a good agreement with the sizes determined by CITPM, enhancing the credibility of its other output parameters.
Język: angielski, wykład osobisty
23 maja 2024
mgr Emil Wilawer (IOA UAM)
Traditional phase curves are created based on the maximum (or average) brightness of the brightness curve at a given phase angle, using dense ground data. However, they are available for a relatively small number of objects. On the other hand, sky surveys, such as Gaia or ATLAS, provide data for a large number of objects, but the data are spread out over time and there are significant changes in the geometry of the observations, making it difficult to obtain high-quality phase curves based on these data alone.
By combining both types of data, it is possible to obtain high-quality phase curves for a large number of objects. In addition, by applying this method to survey data using different filters, it is possible to study the effect of the filter used on the observation results. With an exponentially increasing number of incoming data and new, larger surveys of the sky planned, this method makes it possible to make efficient use of such data and obtain previously unavailable information about asteroids.
Język: angielski, wykład osobisty
16 maja 2024
dr Vincent Robert (IMCCE & IPSA, France)
The NAROO program has been created at Paris Observatory, Meudon, as a unique centre dedicated to the digitization and the analysis of old astro-photographic plates for scientific purposes, only.
The renewed interest about photographic plates concerns the expansion of the database of transient objects evolving in time, since 1) digitization now makes it possible to measure images with a high level of accuracy and to identify all the available objects, 2) the arrival of the Gaia reference catalogs allows to realize reductions for past observations with today accuracy. The information extracted from such materials can be of an astrometric, photometric, and spectroscopic nature, when not purely imaging, with consequences in planetology, near-Earth asteroid risk assessment, astrophysical phenomena, and general relativity, to mention but a few. We will present technical details about the installation, then results of the first large scientific campaigns derived form planetary plates (Jupiter) and Sky surveys plates (NEO precoveries).
Język: angielski, wykład zdalny
09 maja 2024
prof. Gracjan Maciejewski (IA UMK)
Hot Jupiters, giant planets on tight orbits, have been perceived as loners devoid of planetary companions in close orbital proximity. However, recent discoveries based on space-borne precise photometry have revealed that at least some fraction of those giant planets coexist with low-mass planets in compact orbital architectures. The origin of hot Jupiters is a long-lasting question in the planetary formation and evolution theory. Three main pathways are proposed to explain the formation of those planets: in situ formation, disk migration, and high eccentricity tidal migration. The question of the dominant path still needs clarification, and the answer is hidden in the architectures of those systems. In my talk, I will share the results of an ongoing project aimed at searching for transiting planetary companions to hot Jupiters, including a tale on the WASP-84 system.
Język: angielski, wykład osobisty
25 kwietnia 2024
mgr Karolina Dziadura (IOA UAM)
Asteroid studies are pivotal in unravelling the mysteries of the Solar system’s formation, as well as understanding planetary systems and Earth’s water origins. This research focused on determining asteroid sizes through occultation data and devising an effective method to leverage the precise Gaia DR2 and DR3 asteroid data for analyzing the Yarkovsky effect.
Leveraging Gaia’s robust asteroid astrometry, alongside radar and terrestrial observational data, our research advances orbit computation efforts, with a special emphasis on identifying non-gravitational transverse accelerations. We introduced and validated an innovative astrometry weighting scheme, which factors in diverse observational variables, thereby enhancing data reliability. Ultimately, the analysis of the Yarkovsky effect on asteroids allowed for determining their densities, providing crucial parameters for understanding the physical properties and evolution of these minor celestial bodies.
The advent of Gaia’s stellar measurement accuracy has revolutionized the observation of occultation events, granting us deeper insights into asteroid characteristics. This is particularly critical for potentially hazardous asteroids (PHAs), where exact size and orbit determinations are pivotal for impact monitoring. The assessment of the Yarkovsky effect has facilitated the determination of asteroid densities, shedding light on these minor celestial bodies’ physical properties and their evolutionary trajectories.
Additionally, this study delves into the utilization of occultation data, integrating its inherent uncertainties to accurately ascertain asteroid sizes. The meticulous computation of orbits, employing various observational spans, and the analysis of a few PHAs underscore the research’s contribution to precise orbit prediction. By factoring in phenomena such as the Yarkovsky effect, we have significantly refined orbit determination processes, marking substantial progress in the realm of PHA monitoring.
Język: angielski, wykład osobisty
18 kwietnia 2024
dr Krzysztof Langner (IFAC-CNR & Università di Padova & IOA UAM)
In 2022 the DART mission spacecraft impacted the asteroid Dimorphos, the secondary body of the binary Didymos system, ejecting a large number of dust particles, rocks and boulders. The ESA Hera mission will reach the system in 2026 for post–impact studies and possible detection of orbiting fragments. We investigate the long term dynamics of the large boulders ejected by DART to test if any of these objects survive in orbit until the arrival of the Hera mission. To model the dynamics of the boulders we use a numerical model which includes the gravity of non-spherical Didymos and Dimorphos, the solar gravity and the radiation pressure. The SPICE kernels are used to define the correct reference frame for the integration. The dynamics of the boulders is highly chaotic and 1% of the initial boulders survive at least for 4 years on quasi–stable orbits. These orbits are characterised by wide oscillations in eccentricity in antiphase with those in inclination (including spin flips), a mechanism similar to the Kozai one. This behaviour may protect these bodies from close encounters with both asteroids. We also compute the distribution on the surfaces of the asteroids of sesquinary impacts which may influence the dust emission, after the initial DART impact, and the surface composition of the asteroids. The probability of observing boulders by the mission Hera is small but not negligible and an almost constant flux of escaping boulders is expected in the coming years since their lifetime after the DART impact covers a large time interval. Most of re–impacts on Dimorphos occur in the hemisphere opposite to the impact site, preferentially close to the equatorial plane.
Język: angielski, wykład zdalny
11 kwietnia 2024
prof. Paweł Kankiewicz (UJK)
Asteroids in retrograde orbits, known briefly as retrograde asteroids, have relatively short lifetimes in the Solar System. It can be assumed that almost all of them are orbiting in highly chaotic trajectories. Quantitatively, it is possible to estimate this using suitable parameters that measure the rate of chaotic expansion of close trajectories. Since we are mostly dealing with problems solved strictly numerically, an obvious solution is the application of Lyapunov indicator and a related parameter known as MEGNO (Mean Exponential Growth factor of Nearby Orbits). In the current work, I would like to present a novel and very flexible software that allows the simulation, quantitative estimation and imaging of the chaotic behaviour of retrograde asteroids, designed using astronomical Python language modules. The comprehensive solution allows flexible use of astronomical databases, instant updating with new observational data, testing of different perturbation models and linking results to observational errors.
Język: angielski, wykład osobisty
14 marca 2024
prof. UAM dr hab. Anna Marciniak (IOA UAM)
Asteroid Justitia is a special main-belt object, being an extremely red body with a steeper spectral slope than any other D-type asteroid. Conversely, its spectral and polarimetric properties resemble organics-rich Centaurs and trans-Neptunian objects. For this reason, it was recently chosen as a main target of the MBR space mission.
It is crucial for space mission planning and operations to have in advance the best estimate of the target size, spin, shape, and properties of the surface. In particular, the size determination was in high demand before the extensive stellar occultation campaign in August 2023, for stations deployment and observation planning.
We utilised multiple lightcurves from our campaign on slow rotators and from the literature to reconstruct the spin and shape of Justitia via lightcurve inversion. Then we applied the Convex Inversion Thermophysical Model to simultaneously optimise the fit to visible lightcurves and to thermal data from infrared space observatories. We will present the most precise physical model of Justitia possible before the occultation campaign.
Język: angielski, wykład osobisty
07 marca 2024
mgr Aleksandra Leśniewska (IOA UAM)
Dust is a key component of the interstellar medium. The mechanism of dust removal from galaxies has not been completely understood yet. I will address this issue by the analysis of 2050 dusty early-type galaxies, in which star formation has a much lower rate than what their masses could imply, yet an unnaturally large amount of dust is observed. The analysis is conducted on a sample that differs from previous works not only in the number of objects, but most of all in a wider range of parameters. Based on already published data (GAMA and eFEDS) as well as on never-before-published data from LOFAR we are able to determine mechanisms which are responsible for the observed dust loss and estimate the dust removal timescale observed in dusty early-type galaxies.
Język: angielski, wykład zdalny
1 luty 2024
prof. dr hab. Edwin Wnuk (IOA UAM)
Język: polski
25 stycznia 2024
dr Jakub Nadolny (IOA UAM)
In this talk, I will focus on LGalaxies2020 semi-analytic models run on top of Millennium Simulations. The Millennium Simulations provide a cosmological volume (with a side length of ~700 Mpc) in a concordance LCDM cosmology.
In particular, I will focus on a selected sample of early-type galaxies, including their history, to address how and why these galaxies have quenched their star formation. One crucial factor in the quenching of star formation involves the elimination of the cold interstellar medium (ISM) from a galaxy. However, it is not yet clear which quenching mechanisms are dominant. Here, we study the decline in atomic hydrogen and dust mass in a statistically significant sample of massive (M*>10^10Msun) simulated early-type galaxies in a redshift range between 0.02 and 0.32. We find agreement with previous observational works, considering the timescales of ISM removal. Furthermore, we show that black hole growth, together with radio mode accretion and its feedback, controls the amount of cold and hot gas in galaxies, leading to quenching. This is a consequence of a merger event at some point in the evolution of individual galaxies. Moreover, we recover the observed relation between dust mass and star formation rate for actively star-forming galaxies, as well as for passive early-type galaxies. We conclude that merger-driven morphological transformation is a key event that shapes the evolution of simulated galaxies.
This work is a continuation of a series of papers about ‘The fate of the interstellar medium in early-type galaxies’ (see Michałowski et al. 2019, 2024; Leśniewska et al. 2023).
Język: angielski, wykład zdalny
18 stycznia 2024
dr Przemek Mróz (OA UW)
Gravitational-wave detectors – LIGO, Virgo, and KAGRA – have revealed a population of massive black holes whose origin is still a subject of vigorous debate. Understanding the population of black holes in the Milky Way is therefore of key importance for understanding and putting into the astrophysical context the LIGO/Virgo/KAGRA discoveries.
Gravitational microlensing remains the only viable technique which enables us to detect and directly measure masses of isolated stellar remnants, especially neutron stars and black holes. In this talk, I will present the recent advancements in the field of gravitational microlensing, which have led to the discovery of the first isolated stellar-mass black hole in the Milky Way and which will pave the way for future similar discoveries. I will present how astrometric and interferometric observations of gravitational microlensing events allow us to detect and characterize isolated neutron stars and black holes. Finally, I will discuss whether black holes of different sizes can make up dark matter.
Język: angielski
11 stycznia 2024
mgr Sofiia Mykhailova (IOA UAM)
The project at hand is centered on observational studies of primitive asteroids, addressing the challenges posed by the lack of spectral information about their surface compositions. While most compositional studies have focused on visible-near-infrared (VIS-NIR) wavelengths, the study highlights the distinct near-ultraviolet (NUV) absorption feature in low-albedo asteroids, suggesting variations in surface composition related to iron content and hydration history. The significance of NUV studies is underscored by their potential to detect hydrated minerals and organic materials, providing crucial insights into asteroid history and the effects of space weathering. In this talk I will present the first results of observations of asteroids in NUV-VIS range, obtained using the 10.0-m SALT telescope in South Africa, during November-December 2023.
Język: angielski
21 grudnia 2023
Dominik Cieślak (University of Maryland Baltimore County)
This presentation provides an overview of the techniques and instruments employed in the remote sensing aerosols in Earth’s atmosphere. The discussion will focus on the role of remote sensing in enhancing our comprehension of cloud development and its direct correlation with air pollution. The engineering segment of the presentation will particularly accentuate the design of the HARP instruments, including the environmental tests that these satellite instruments must undergo before being considered for NASA space missions.
Język: angielski
14 grudnia 2023
dr Paolo Tanga (Observatoire de la Côte d’Azur, Nice, France)
The traditional view of a clear separation between astrometry of asteroids, and observations devoted to determine their physical properties (shape and rotation for instance) is challenged by data collected by the Gaia mission of ESA. The reason is that Gaia astrometry, at least for a fraction of the asteroids, contains the signature of effects related to their orientation in space, their size, or the presence of satellites. In this situations, an optimal exploitation of the data includes the optimal modeling of such physical characteristics, a complex task whose implications have still to be fully exploited. In this talk I will detail in particular the possible signature of binarity, an ongoing search. I will also recall the interest of the more indirect, but strong impact of Gaia on the asteroid occultation technique, that has never been so powerful before.
Język: angielski
7 grudnia 2023
prof. UAM dr hab. Piotr A. Dybczyński (IOA UAM)
Autorzy:
Piotr A. Dybczyński, Małgorzata Królikowska-Sołtan, Przemysław Bartczak, Edyta Podlewska-Gaca, Krzysztof Kamiński, Jakub Tokarek, Krzysztof Langner, Jos de Bruijne
Abstract:
In the long-period comets dynamical studies we have to cope with the increasing knowledge on the stars that can act as their perturbers. As a part of our long standing project we made available two databases: stellar: https://pad2.astro.amu.edu.pl/StePPeD/ and cometary: https://pad2.astro.amu.edu.pl/CODE/
We found several important stellar perturbers but the most important seem to be the star HD 7977. According to the Gaia DR3 astrometry this star (of 1 solar mass) passed near the Sun 2.47 Myr ago at a distance of 0.011 pc (~2300 au) ! We discuss the uncertainty of this result, its possible consequences and show some examples of its impact on the Solar System small bodies dynamics.
Język: angielski
30 listopada 2023
mgr Paweł Koleńczuk (IOA UAM)
Very small Near-Earth asteroids (diameter less than 200 m), due to their size, can usually be observed for a short time during close approaches to the Earth, after which it is often necessary to wait several or dozens years for another approach. Therefore, not many of these objects are well characterized, for example, only about 1% of them have a designated taxonomic type. I am going to present the issues of observation and methods of obtaining colour indices and taxonomic type of NEOs.
Język: angielski
23 listopada 2023
mgr Fabian Kaczmarek (IOA UAM)
Symbiotic stars (SySts) represent an example of close binary systems in which a hot, compact object, most often a white dwarf, accretes material from a cool component, usually an evolved red giant. Such systems are characterized by the longest orbital periods among interacting binary stars. In order to spatially resolve the components of SySts, high angular resolution of astronomical observations is required. Optical, long-baseline interferometry provides an ideal method for this task, as it allows to directly and very precisely study such binary stellar systems, e.g. measure the radii of their components with spatial resolution of the order of milli-arcseconds. Here I would like to present the results of analysis of the interferometric observations that were made for the symbiotic recurrent nova RS Ophiuchi. The data was obtained using the ATISSE/VLTI instrument. I was able to determine the size of the emitting regions and – as the data was obtained for two different observational epochs – follow the expansion of the ejected matter.
Język: angielski
16 listopada 2023
prof. Karri Muinonen (University of Helsinki)
Photometric inversion has been extensively used to infer the spin and shape properties of asteroids from dense ground-based lightcurves. The high-precision sparse photometry provided by Gaia has enabled studies of asteroid phase functions. Gaia Data Release 3 (DR3) contains photometric observations of more than 150,000 asteroids (Tanga et al., Astron. & Astrophys. 674, A12, 2023). We consider the rotation periods, pole orientations, shapes, and photometric slopes for over 22,000 asteroids that have at least 25 Gaia observations, using ellipsoid and general convex shape models. We characterize the uncertainties of the solutions by using a Markov chain Monte Carlo approach (Muinonen et al., Astron. & Astrophys. 642, A138, 2020). We complement the photometric slopes with DR3 spectroscopy (Gaia Collaboration, Astron. & Astrophys. 674, A35, 2023). The full spectroscopic dataset includes 57490 asteroids. After selecting asteroids with both spectra and photometric slopes and after filtering for the highest-quality spectral points, we are left with 5783 asteroids. Constructing a feed-forward, fully connected neural network, we find that the most reasonable classification (maximum number of classes with high overall accuracy) comes from classifying the asteroids into the taxonomic classes C, S, X, and D. The accuracy of the classification is about 80%. Finally, classification with only the spectroscopic parts would decrease the accuracy.
Język: angielski
9 listopada 2023
dr Jolanta Grala-Michalak (Wydział Matematyki i Informatyki UAM)
Pięćsetpięćdziesiąta rocznica urodzin Mikołaja Kopernika jest dobrą okazją do głębszego poznania twórcy i jego dzieła.
Astronomia jest nauką, której uprawianie wymaga doskonałej znajomości różnych dziedzin matematyki. Jednak przeciętna wiedza nie wystarczy do zbudowania modelu praw rządzących światem, takiego jak model Kopernika Układu Słonecznego – do tego trzeba być też wybitnym matematykiem. Celem wykładu jest przedstawienie sylwetki Kopernika jako matematyka na podstawie prac historyków (Łubieńska-Iwaniszewska, Rosińska) oraz matematyków (Mioduszewski, Neugebauer, Zielińska).
W toku wykładu zostaną przedstawione podstawowe fakty dotyczące zapisu formuł matematycznych w czasach Kopernika oraz główne rozważane wtedy problemy matematyczne. Omówione zostanie zagadnienie opisu ruchu ciała poruszającego się po epicyklu na dyferensie oraz sposoby tworzenia i korzystania z ówczesnych tablic funkcji trygonometrycznych. Pokazane zostanie także, jak wpłynęły na rozwój matematyki, nie tylko XV-wiecznej, badania astronomiczne Kopernika.
Główny nacisk zostanie położony na przedstawienie wiedzy matematycznej dostępnej autorowi „De revolutionibus”, opis jego matematycznych dokonań oraz ich wpływ na współczesną matematykę.
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O wykładowcy. Doktor nauk matematycznych w dyscyplinie statystyka matematyczna (2001). Aktualnie zatrudniona na stanowisku starszego wykładowcy na Wydziale Matematyki i Informatyki UAM. Zainteresowania naukowe obejmują rachunek prawdopodobieństwa, statystykę matematyczną oraz zastosowania matematyki. Aktywna popularyzatorka matematyki i jej zastosowań.
Język: polski
26 pażdzienika 2023
mgr Justyna Olszewska (IOA UAM)
In stellar research, spectroscopy and photometry play a key role in obtaining complex insights into stellar properties and processes. My study focuses on the analysis of spectroscopic data obtained from the Global Astrophysical Telescope System (GATS) for selected Galactic Cepheids. I determined changes in atmospheric parameters and chemical composition in relation to the pulsation phase. To complete my study, I also analyzed photometric data collected by the TESS space observatory. The combination of spectroscopy and photometry provides a more comprehensive understanding of Cepheids and their characteristics.
Język: angielski
12 października 2023
Seminarium odwołane (obchody 30 rocznicy powstania Wydziału Fizyki UAM)
W roku akademickim 2022/2023 wystąpili:
22 czerwca 2023
dr Bartłomiej Zgirski (CAMK)
Distance determinations are among the fundamental tasks in astronomy. They not only allow for the proper calibration of the energetics of different astrophysical phenomena but are also crucial for determining important cosmological parameters, including the Hubble parameter.
There is no single universal method for cosmic distance determinations. In practice, we work with the cosmic distance ladder, where short-range methods calibrate zero points of long-range methods. The most precise and accurate distances to astrophysical objects and systems are obtained using geometric methods such as parallax or relying on the analysis of detached eclipsing binary stars. These methods allow us to anchor our secondary methods applied in the determination of distances to nearby galaxies. Classical Cepheids, the tip of the Red Giant Branch, and carbon stars are representatives of the secondary distance indicators. The final rung of the ladder is associated with distances to galaxies in the Hubble flow obtained using properly calibrated luminosities of supernovae.
An important problem in modern astronomy is the discrepancy between values of the Hubble parameter obtained from observations of the early and late Universe, known as the Hubble tension. Namely, the model-dependent value based on the analysis of the cosmic microwave background observed with the Planck space observatory does not agree with the value based on the determination of the parameter using supernovae calibrated by classical Cepheids. This puzzling issue could be associated with the need to check for unaccounted systematic errors of the used distance determination methods or the necessity to revise the Lambda cold dark matter cosmological model. Thus, it is important to use, in parallel, different distance determination methods at the same scales in order to check for potential systematic biases that depend on the used method.
As a member of the Araucaria Project, an international team of astronomers working on the cosmic distance scale, I will highlight the methods we use. I will also present a new Polish observatory in the Chilean Atacama Desert that will allow us to gather both photometric and spectroscopic data in the optical and near-infrared domains for the purpose of our project and beyond.
Język: angielski
15 czerwca 2023
dr Justyna Gołębiewska (IOA UAM)
Prezentacje studentów przedstawiające koncepcje i studium wykonalności misji kosmicznej do wybranego obiektu Układu Słonecznego. Koncepcje misji zostały przygotowane w ramach przedmiotu “Astronomia Układu Słonecznego” prowadzonego przez dr Justynę Gołębiewską metodą Problem-based learning.
Język: polski
1 czerwca 2023
prof. dr hab. Tadeusz Jopek (IOA UAM)
The Shower Database (SD) of the Meteor Data Center (MDC) had been operating on the basis of stream-naming rules which were too complex and insufficiently precise for 15 years. With a gradual increase in the number of discovered meteor showers, the procedure for submitting new showers to the database and naming them led to situations that were inconsistent with the fundamental role of the SD — the disambiguation of stream names in the scientific literature. Our aim was to simplify the meteor shower nomenclature rules. We proposed a much simpler set of meteor shower nomenclature rules, based on a two-stage approach, similar to those used in the case of asteroids. The first stage applies to a new shower just after its discovery. The second stage concerns a repeatedly observed shower, the existence of which no longer raises any doubts. Our proposed new procedure was approved by a vote of the commission F1 of the IAU in July 2022.
Język: polski
25 maja 2023
dr Grzegorz Nowak (Instituto de Astrofísica de Canarias and Universidad de La Laguna and Nicolaus Copernicus University)
The basic characterisation of planets (internal structure, formation history and possible atmospheric composition) starts with a measurement of their masses and radii. The need to know both of these quantities is a motivation for a great development of the ground- and space-based transit surveys and for a continuous importance of the radial velocity (RV) technique, which together became a tandem of mutually supporting observing techniques. Having the three main planetary quantities, i.e. mass, radius and mean density, we are in a position to study the planets’ internal structure as well as their formation and evolution, by placing them within mass-radius and mass-density diagrams. Precise RV measurements from 3-4-metre class telescopes are fundamental in determining planetary masses, in filling these diagrams, and in explaining the large scatter in fundamental properties, especially for the smallest planets of 1-4 Earth radii.
In this talk I am going to present recent results of radial velocity follow-up of Kepler-K2 and TESS planet candidates with TNG/HARPS-N and CAHA/CARMENES instruments in a framework of KESPRINT and CARMENES consortia. These results include sub-Neptune planets around nearby M dwarfs LTT 3780 (TOI-732) and G 9-40 (K2-313, TOI-5097), an ultra-short-period, 1.7 R_Earth planet around a solar-type star HD 20329 (TOI-4524), sub-Saturn around G7V star K2-280, and a planetary system around G9V star HD 191939 (TOI-1339), including HD 191939 g – Uranus-mass planet in the habitable zone with an orbital period of ~300 days.
Język: angielski
18 maja 2023
mgr Martin Solar (IOA UAM)
Core-collapse supernova (SN) explosions mark deaths of massive stars. They are responsible for the production of heavy elements and for the energetic feedback halting star formation, that have a profound impact on galaxy evolution.
Details of these processes depend on the stellar progenitors of a given SN type, however, the progenitors of Type Ic SNe (without hydrogen and helium lines in their spectra) have not been confirmed in pre-explosion images and it is unclear if they originate from the core-collapse of very massive stars (> 30 M⊙) or from less massive stars in binary systems (10 − 20 M⊙).
In this walk I will show that Type II and Type Ic SNe are located in environments with similar molecular gas densities, showing that their progenitors have comparable lifetimes and therefore similar initial masses (2σ range of 10–13 M⊙ for Type Ic SN progenitors, assuming an initial mass of Type II SN progenitors of 11 M⊙).
Our finding supports binary models for most Type Ic SNe, arguing that the lack of hydrogen and helium in their spectra is due to the interaction with a companion star, responsible for stripping the outer layers. This can be used to compute the SN metal production, and be implemented in sub-grid processes in order to improve SN feedback and chemical mixing in numerical cosmological simulations.
Język: angielski
11 maja 2023
dr Dagmara Oszkiewicz (IOA UAM)
The early Solar System was populated with numerous differentiated (into iron core, silicate mantle and crust) planetesimals. These objects evolved and grew into planets. Some were destroyed in collisions. Crust fragments of those bodies can still be observed in the main asteroid belt as basaltic V-type asteroids. In this project we have determined spins and shapes of V-type asteroids with the aim to reconcile them with numerical simulations of Nesvorny et al. 2008 and the planetesimal formation theory of Bottke et al. 2006.
Język: angielski
20 kwietnia 2023
dr Krzysztof Kamiński (IOA UAM)
The time scale characterising the vast majority of observed astronomical phenomena is many orders of magnitude larger than one second. However, in the case of asteroid occultations and especially in the case of the astrometry of artificial, low-Earth orbit satellites, the required accuracy is much greater, up to 0.1 millisecond. Such accuracy is difficult to achieve and verify. Therefore, in recent years, several devices specifically designed for testing the absolute timing accuracy of a camera have been developed. The findings obtained with the newest camera test device shall be presented.
Język: angielski
13 kwietnia 2023
dr Agata Rożek (University of Edinburg, Scotland)
On 26th September 2022 NASA conducted the first asteroid deflection test using the DART spacecraft. The probe hit a small moon Dimorphos orbiting a near-Earth asteroid Didymos. One of the principal mission aims was to change orbital period of Dimorphos in the asteroid system in a measurable way, and it was a smashing success. The collision aftermath was closely monitored from space and ground, including by the observers from Edinburgh’s Institute for Astronomy. We used the Danish 1.54m telescope in Chile, the VLT, and a brand-new telescope in Kenya. The global observing campaign was designed for determining the period change and monitoring post-impact ejecta. The orbital change was measured to be -33±1 min, and confirmed with two different observational methods: the optical observations and Doppler-delay radar imaging. I’ll present an overview of the DART mission and Edinburgh’s contribution to the Didymos/Dimorphos observing campaign.
Język: angielski
16 marca 2023
Mark Trueblood (Winer Observatory, Arizona)
Introduction to the Winer Observatory
Język wykładu: angielski
9 marca 2023
prof. UAM dr. hab Tomasz Kwiatkowski (IOA UAM)
Język: angielski
2 marca 2023
Sprawy organizacyjne
Język: polski
2 lutego 2023
Sprawy organizacyjne
Język: polski
26 stycznia 2023
mgr Karolina Dziadura (IOA UAM)
We determine the non-gravitational transverse acceleration (the Yarkovsky effect – A2) using Gaia DR3 asteroid astrometry for 446 Near Earth Asteroids including 93 Potentially Hazardous Asteroids and 54 094 IMBA and Mars Crossing asteroids. For orbit determination, we used OrbFit software and the differential correction method. The software has been subject to years of testing and validation and is currently being used by the European Space Agency. We used all data available in Minor Planet Centre (MPC), all radar data and all Gaia DR3 observations and a new, more complex weighing scheme for asteroid astrometry. Thanks to Gaia DR3 and the new weighing scheme we improved the orbit uncertainties and detected the reliable A2 value for 60 Near Earth Asteroids, including 25 new detections and 35 improvements in signal-to-noise ratio. By adding a relatively small amount of ultra-precise astrometry from Gaia DR3 we significantly improved the orbit parameters for studied objects.
Język: angielski
19 stycznia 2023
dr Regina Rudawska (ESA)
Since Jan 2009, European Space Agency (ESA) has a so-called ’Space Situational Awareness’ programme, addressing, among other points, the topic of Planetary Defence. Planetary Defence means to ensure that we know about asteroids potentially hitting our planet, and what to do about it. In my talk I will present the overview and the main tasks of Planetary Defence Office (PDO). More at the technical portal
http://neo.ssa.esa.int, focusing on providing information on the scientific and technical community.
Język: angielski
12 stycznia 2023
dr Oleksyi Golubov (IOA UAM and Kharazin University, Kharkiv, Ukraine)
I’ll review the influence of the radiation pressure forces on the dynamics and evolution of asteroids, the so-called Yarkovsky and YORP effects. Special attention will be devoted to the theoretical description of these effects, their significance for the evolution of asteroids, and my own results: the tangential YORP effect and possible dynamic equilibria for asteroids subject to YORP.
Język: angielski
5 stycznia 2023
dr Dagmara Oszkiewicz (IOA UAM)
In this work, we performed spectral analysis of V-type asteroids observed by the Gaia mission. Data Release 3 increases the sample size of known V-types by more than three times as compared to the literature. Using the data provided by Gaia we identified ~2000 plausible V-type asteroids. About 350 of them successfully pass our data validation criteria. We determined spectral parameters of the best sample. We confirm that the V-type asteroids in the middle and outer part of the main belt show distinct spectral properties compared to typical vestoids. In the inner main belt, we found a great diversity of spectral parameters among the V-types in all populations. Number of asteroids show band depths even greater than that of (1459) Magnya. Furthermore, some objects present 0.9~\mu m band-centers more than one standard deviation away from the typical value for vestoids. Overall our results indicate that the inner main belt may contain remnants of multiple differentiated planetesimals, not just (4) Vesta.
Język: angielski
22 grudnia 2022
dr Oleksyi Golubov (IOA UAM and Kharazin University, Kharkiv, Ukraine)
Język: angielski
Seminarium odwołane
15 grudnia 2022
prof. Jarosław Włodarczyk Instytut Historii Nauki, PAN Warszawa
In this paper I intend to discuss the astronomical content of a set of 22 letters written in the years 1648–1654 and exchanged by Johannes Hevelius (1611–1687) with Maria Cunitia (1610–1664) and her husband, Elias von Löwen (Crätschmair, c. 1602–1661), a couple based in Silesia. Maria Cunitia is acknowledged for her Urania Propitia (1650), an innovative adaptation of the mathematical astronomy of Johannes Kepler’s Rudolphine Tables (1627). In turn von Löwen authored astronomical calendars and ephemerids.The letters can be seen as an extraordinary example of the exchange of thoughts involving, on the one hand, a representatives of the mainstream European astronomy of the 17th century (Hevelius) based in an acknowledged scientific center (Gdańsk) and, on the other, astronomers working in the periphery of then scientific Europe. The correspondence features several significant astronomical themes, which cast new light on the activities of astronomers in the first half of the 17th century, and even on the chronology of discoveries. These include telescopic observations of the positions of the planets made to verify the accuracy of astronomical tables, studies of the optical libration of the Moon in the period preceding Galileo Galilei and Hevelius, and discussion of the usefulness of various observational tools such as the telescope.
Język: angielski
8 grudnia 2022
Anne-Charlotte Perlbarg (Observatoire de Paris)
Potentially Hazardous Asteroids (PHAs) are small bodies making very close encounters with the Earth. PHAs are a real danger and depending on their size, an impact may have catastrophic consequences. The knowledge of their dynamics is essential for the purpose of an international program of planetary defense. Thus, accurate astrometric measurements acquired over a large time span are important to provide reliable orbits and impact probability, which often need to take into account accelerations such as Yarkovsky effect. Photographic plates made during the 19th and 20th century consist of a substantial source of old observations of Solar System objects. From existing databases, we have identified precovery observations of PHAs: i.e. fortuitous observations made before its discovery. We used the NAROO machine to digitize the plates and realized the astrometric reduction with Gaia eDR3 reference star catalog. Metadata have been verified and corrected through the measurement of the position of Main Belt Asteroids in the field of view. We added the results to observation dataset of PHAs to define new orbital solutions and detect Yarkovsky effect with the NIMA software. It shows an improvement of the accuracy of their new ephemeris depending on the asteroid. Our analysis demonstrates the interest of using precovery observations from photographic plates. It allows us to better assess the risk and impact probability of PHAs in the context of Planetary Defense or Space Situational Awareness.
Język: angielski
1 grudnia 2022
prof. Wojciech Dimitrow (IOA UAM)
The application of the Wilson-Devinney method to model star-planet pairs will be presented. The possibility of studying fainter effects such as reflected light, ellipsoidal variations, and spots on the surface of the parent star will be discussed. In addition, an overview of recent results in the study of exoplanets will be presented.
Język: angielski
24 listopada 2022
prof. David Vokrouhlicky (Charles University, Prague)
Asteroid families are groups of asteroids that share similar heliocentric orbits. They result from a collision between a parent object of the family and sufficiently large projectile; what we see now are fragments from this event. As such, data about asteroids in families can offer a unique probe of the fragmentation process and interior properties of the parent body. In this talk I will focus on yet another aspect, namely on our ability to determine epoch when in the past the family formed (thence the age of the family). Hunt for very young families have led not only to new methods of discovering families themselves, but also an entirely new population of asteroid pairs. Unlike families, the pairs are predominantly formed by rotational fission of the parent body, and represent siblings to asteroid binaries. I will finish my talk with discovery of a stunningly young pair.
Język: angielski
17 listopada 2022
dr Yurij Krugly (IOA and Kharazin University, Kharkiv, Ukraine)
The investigation of physical properties of NEAs through systematic CCD observations has been carried out at the Institute of Astronomy of V.N. Karazin Kharkiv National University since 1995. It includes obtaining the rotation parameters, sizes and shapes of NEAs with an increased interest in the study of newly discovered and potentially hazardous objects. The observations are carried out within the framework of wide international cooperation.
In the presentation, I will focus on various aspects and results of these photometric and polarimetric observations:
(1) Discovery and study of binary NEAs;
(2) Observational confirmation of YORP and BYORP;
(3) Estimation of albedo and composition type by polarimetric observations.
Język: angielski
10 listopada 2022
mgr Jakub Tokarek (IOA UAM)
Astronomical Observatory in Poznań started its work simultaneously with the foundation of the Poznań University (Uniwersytet Poznański) in the 1919. In the past one hundred years it had seven principals and dozens of rank-and-file employees. Their work laid the foundations for the current fields of research at the Observatory. In this talk I will try to depict the short profiles of some of these employees.
Język: Angielski
3 listopada 2022
Milagros Colazo (Universidad Nacional de Córdoba, Argentina)
We all know that the brightness of asteroids varies due to different factors. We can see this brightness variation in the Light Curves (magnitude variation due to the asteroid’s rotation about its axis) and the Phase Curves (magnitude variation as the asteroid moves in its orbit around the Sun).
Together with the “Grupo de Observadores de Rotaciones de Asteroides” (GORA), we measure the light curves of dozens of asteroids to obtain the periods and amplitudes of these objects. GORA is an international network of amateur astronomers with whom we publish all our measurements in the Minor Planet Bulletin (MPB).
A significant aspect of my Ph.D. work is to take advantage of the large amount of photometric data provided by the current large astronomical surveys. Using the Gaia sample, we have obtained a catalog of H and G parameters for 9817 asteroids. From this work, “Pyedra” was developed: a software package written in Python that allows fitting different phase curve models to large catalogs of observations. On the other hand, we performed a taxonomic classification of asteroids using the 5 Sloan filters.
It is crucial to prepare statistical and computational tools capable of taking full advantage of the big data revolution on asteroids.
Język: angielski
20 października 2022
prof. Michał Michałowski (IOA UAM)
During this interactive presentation I will discuss with the participants several key properties of gravitational lensing in the context of testing the general relativity theory. I will also discuss in which configurations we should expect lensing. Then I will present what properties of future telescopes (with >15 meter mirrors) are needed to detect stars lensed by the supermassive black hole in the centre of the Milky Way.
Język wykładu: angielski
13 października 2022
dr Łukasz Tychoniec (ESO Garching)
In this talk I will present highlights of first three months since JWST started science operations. Aside from the news-making discoveries, I will present some of our first results of the JOYS collaboration (JWST Observations of Young protoStars). In addition I will put special focus on the exploration of the Solar System with JWST and what it has to offer in studies of small Solar System bodies.
Język wykładu: angielski
6 października 2022
Język wykładu: polski
W roku akademickim 2021/2022 wystąpili:
9 czerwca 2022
dr Magdalena Otulakowska-Hypka (IOA UAM)
Two of only four known symbiotic recurrent novae erupted recently. These very rare events were monitored for the first time by the second-generation instruments at VLTI. Thanks to the ESO DDT channel we were able to react fast and collect VLTI data starting only a few days since the ignitions of both eruptions. We used all three VLTI instruments: PIONIER, GRAVITY, and MATISSE and resolved both objects spatially and spectroscopically. Our observations show complex structures and asymmetries which we model at milliarcseconds scale.
Język wykładu: angielski
2 czerwca 2022
mgr Antoine Choukroun, prof. Anna Marciniak (IOA UAM) (IOA UAM)
With the high quantity of asteroids already discovered and according to techniques used in this field, scientists need a lot of data to characterise them. Today’s data on asteroids is mainly photometry on unresolved targets. It is easy to perform with small telescopes available even to amateur astronomers, with growing degree of automatisation. According to this, huge amounts of quality data are relatively easy to produce. Difficulty for scientist now is to reliably process this amount of data. Some already existing software solutions can be used with simple tools like aperture photometry, but they are not well suited for asteroid tracking or variable seeing conditions. If asteroids are moving fast or if there are some star passages brighter than the asteroid, these apertures could lose the target. It takes a lot of time to monitor algorithms, and finally it is not possible to process much data this way. On the other hand, some attempts to automatise the process have already been developed, but without convincing results.
We present a set of new python packages which automatise asteroid detection and lightcurve production. Also some other features have been already added to this package to help scientists with data analysing like asteroid(s) detection, flexible aperture size, star passage detection, data binning etc. To evaluate it we compared it with scripts based on STARLINK packages, which were extensively used in the past. Results are very similar, and in each tested case the package was in agreement with the results produced with STARLINK.
Język wykładu: angielski
26 maja 2022
prof. Tadeusz Michałowski (IOA UAM)
Streszczenia celowo nie podajemy.
Język wykładu: polski
19 maja 2022
mgr Jakub Tokarek (IOA UAM)
The talk will be based on the doctoral dissertation, which will concern the modelling and refinement of eclipsing binary star models, in particular those located in hierarchical systems. Binary and multiple systems make up the majority of observed stars. Since more than 50% of the stars in the vicinity of the Sun are multiple systems, we can assume that a similar situation occurs throughout the Galaxy. As Gaia provides us with new data on stars, a new method will be developed that allows determination of the probability of physical bonding of two visual components of a system. This method will then be used to discover new hierarchical systems. In addition, it is planned to study the statistical relationship between the physical characteristics of close binary systems and companion stars that are in wide orbits and to use the Wilson-Devinney method implemented in the PHOEBE project to accurately model several eclipsing systems to understand the parameters of the system. Data will come from the PST1 telescope observations (archival and future) and the Gaia space mission.
Język wykładu: angielski
12 maja 2022
prof. Josef Ďurech (Charles University, Prague, Czech Republic)
Photometric observations of asteroids can be used for the reconstruction of asteroids’ shapes and rotations states. So far, the technique of lightcurve inversion has led to convex shape models of several thousand asteroids. I will briefly review the main principles of the lightcurve inversion, discuss its results – the distribution of asteroid spin axes in the main belt and collisional families, and show some “non-standard” cases – changing rotation period due to the YORP effect, non-principal axis rotation, and others.
Język wykładu: angielski
5 maja 2022
Sprawy organizacyjne
Język: polski
28 kwietnia 2022
dr Joanna Drążkowska (LMU Munich, University Observatory)
Questions about the origins of Earth have forever accompanied humans. The classical theory of planet formation, established when the Solar System was the only one we knew, has been recently challenged and is undergoing major changes. In this talk, I will explain how the growing population of planets orbiting stars other than the Sun triggered the revision of this classical theory and outline the new, emerging theory of planet formation. I will pay special attention to the early stages of planet formation when dust grains grow to pebbles and the first gravitationally bound building blocks of planets, the planetesimals, form.
Język wykładu: angielski
21 kwietnia 2022
mgr Leonid Shakun (Odessa National University, Ukraine)
Brief information on the structure of Ukrainian optical tracking networks for the observation of artificial satellites will be presented. I will analyze the measurement precision of the network’s telescopes based on observations of reference objects in 2021. Then, using the Ajisai satellite as an example, I will estimate the accuracy of the prediction of the satellite position as a result of processing the network observations. In the second part of the talk, the opportunities for fast photometric observations at the Odessa Observatory will be presented. I will show the results of our determination of the spin period, spin axis nutation period, and its oscillation amplitude of the Ajisai satellite.
Język wykładu: angielski
7 kwietnia 2022
dr Paweł Kankiewicz (Uniwersytet Jana Kochanowskiego w Kielcach)
Od czasu, gdy odkryto pierwszą planetoidę na orbicie wstecznej (1999), sformułowano różne hipotezy związane z cechami fizycznymi i powstawaniem tego typu obiektów. Fizyczne i orbitalne podobieństwo do komet sugerują pochodzenie z ich hipotetycznego rezerwuaru: Obłoku Oorta. Nowsze hipotezy z kolei nie wykluczają pochodzenia międzyplanetarnego. Przedstawione badania i ich rezultaty to wyniki projektu, w którym kompleksowo zbadano dynamikę ciał na orbitach wstecznych i zweryfikowano scenariusze ich ewolucji orbitalnej. Wypracowano metody badań ich długookresowej ewolucji, a także określono, jak długo żyją i pozostaną na stabilnych orbitach w naszym układzie Planetarnym. Zweryfikowano także w kategoriach statystycznych, jak prawdopodobny jest scenariusz odwrócenia takich orbit na skutek perturbacji. Zbadano także możliwy wpływ efektów niegrawitacyjnych na wyniki.
Język wykładu: polski
31 marca 2022
mgr Aleksandra Leśniewska (IOA UAM)
Dust is a key component of the interstellar medium. The mechanism of dust removal from galaxies has not been completely understood yet. However, dust evolution is not only relevant in the context of interstellar medium, but is also one of the main factors defining the evolution of stars and the entire host galaxy. We will address this issue by the analysis of several thousand dusty galaxies, which are becoming passive. They are elliptical galaxies in which star formation has a much lower rate than what their masses could imply, yet an unnaturally large amount of dust is observed – comparable to the amount of dust in spirals. Recent years have brought a large amount of new observational data containing information about dust emissions in low-redshift galaxies, such as one of the major cosmological and galaxy evolution observation projects, Galaxy And Mass Assembly (GAMA). The analysis is conducted on a Herschel Space Observatory sample that differs from previous work not only in the number of objects, but most of all in a wider range of parameters. This allows the determination of how galaxies get rid of dust and the testing of the mechanism which is responsible for this.
Język wykładu: angielski
24 marca 2022
dr Dorota Skowron (OA UW)
The Milky Way is a spiral galaxy. This is inferred from various methods, such as radio observations of Galactic gas, star counts, as well as from our extrapolation of structures seen in other galaxies. However, these methods are indirect and rely on many assumptions. Precise mapping of the Milky Way is also difficult because we may only observe it from the inside through clouds of gas and dust. In result, the exact picture of our Galaxy is still under debate.
However, distances can be accurately measured to Classical Cepheids, which are young pulsating variable stars. I will present a new comprehensive picture of our Galaxy in three-dimensions based on the positions in the sky and precisely measured distances of thousands of these objects.
Język wykładu: angielski
17 marca 2022
dr Toni Santana-Ros (Univ. de Barcelona/Univ. de Alicante)
Almost every day, we point our telescopes at recently discovered Near-Earth Objects (NEOs) with the aim of enhancing their –still– preliminary orbit. The large majority of these discoveries are coming from the major surveys in this field, such as Pan-STARRS, the Catalina Sky Survey or ATLAS.
The story of 2020 XL5 began in December 2020, when it was detected by the Pan-STARRS1 survey at Haleakalāa Observatory in Hawaii. Observations followed during the next few days, and some of the preliminary orbit determinations pointed out the possibility that the object could be librating around the 4th Lagrangian point of the Sun-Earth system. This would make it the second known Earth Trojan asteroid! But the confirmation of this discovery wasn’t a bed of roses…
In this talk, we will learn about the story of a group of brave astronomers who defeat all the villains in their way to discover the second Earth Trojan asteroid.
Język wykładu: angielski
10 marca 2022
dr Edyta Podlewska-Gaca, dr Krzysztof Langner (IOA UAM)
W referacie przedstawiony zostanie projekt “Europlanet-2024-Infrastruktura Badawcza”, realizowany przez IOA przy współpracy z kilkudziesięcioma zagranicznymi instytucjami w ramach programu Horyzont 2020.
Omówiony zostanie zarys projektu, jego główne cele i prace jakie zostały wykonane w IOA w celu stworzenia systemu alertów.
Język wykładu: polski
3 marca 2022
mgr Joachim Krüger (IOA UAM)
In this talk, I will introduce the problem of determining the atmospheric parameters and present results obtained during my master’s thesis. Atmospheric parameters, i.e., effective temperature, surface gravity, metallicity, micro- and macroturbulence, and detailed chemical composition, describe the state of the stellar atmosphere. Their determination is the first step in a specific stellar analysis.
In my work, I calculated the atmospheric parameters for selected 45 stars of A- and F- types observed in the Kepler field. For the spectral analysis, I used high-resolution spectroscopic data from the ESPaDONS spectrograph (CFHT 3.6-m). The atmospheric parameters and rotational velocities were calculated using the iSpec code with spectrum synthesis technique.
I will also briefly introduce further and future works for the presented sample of stars at the end of the talk.
Język wykładu: angielski
24 lutego 2022
dr Jakub Nadolny (IOA UAM)
In this talk, I will focus on the molecular gas content of star-forming galaxies. The selection process was based on the presence of gamma-ray bursts (GRBs), and the availability of IR- or radio-based star formation rates (SFRs). A total of four galaxies were selected. Using observations (PI: M. Michałowski) of atomic carbon [CI](1-0) emission, we were able to estimate an upper limit of [CI](1-0) line luminosities. Using three different methods
we converted luminosities into the molecular gas mass for our GRB host galaxies.
A compilation of star-forming galaxies with [CI](1-0) fluxes is used to compare our findings. As a preliminary result, we find a molecular gas deficiency for galaxies with robust measurements. Furthermore, comparing
the molecular masses estimated based on CO, we find that [CI]-based masses are lower by about ~1.3 dex. Since the [CI] atomic gas has been shown to trace the bulk of the molecular gas, we argue that the discrepancy of the
results is due to the overestimated conversion factor (alpha_CO) used in previous work. Furthermore, since the GRBs are preferentially found in the metal-poor galaxies (i.e. below solar metallicity), we argue that due to
the mass-metallicity relation, the most massive (i.e. log(M*) > 10) galaxies need to lower the metal content for example via metal-poor gas inflow, or a minor merger with the metal-poor galaxy in recent past.
In the second part of the talk I will comment on my PhD investigation within the OTELO survey (if I have some time left).
Język wykładu: angielski
27 stycznia 2022
mgr Ewa Śreniawska (IOA UAM)
Delta Cet jest jedną z najdłużej badanych gwiazd typu beta Cephei. Pierwsze obserwacje zmienności sięgają początków XX wieku. W połowie lat 60. ubiegłego stulecia zaobserwowano zmianę okresu pulsacji. Kolejne badania potwierdziły to, a większość badaczy preferowała model ze stałym tempem zmian okresu pulsacji, których pochodzenia dopatrywano się w ewolucji gwiazdy. Wyniki dotychczasowych badań nie pozwoliły jednak na uzyskanie spójnego i jednoznacznego wyjaśnienia obserwowanych zmian.
W latach 2014-2018 została przeprowadzona spektroskopowa kampania obserwacyjna przy pomocy teleskopów systemu GATS (Global Astrophysical Telescope System), która zgromadziła ponad tysiąc widm wysokiej rozdzielczości tego obiektu. Dane te stanowią największy jednorodny zbiór obserwacji spektroskopowych dla tej gwiazdy.
Analiza zarówno danych historycznych jak i naszych obserwacji, że najbardziej prawdopodobną przyczyną zmian okresu pulsacji jest obecność składnika wtórego o minimalnej masie 1,1 M_sun na orbicie o okresie około 169 lat.
Język wykładu: polski
20 stycznia 2022
prof. Anna Marciniak (IOA UAM)
Slowly rotating asteroids turn out to be abundant, yet little is known about their physical properties. In our wide campaign we observe them in a rich network of small telescopes (including amateur observatories), gathering lightcurves in the visible from multiple apparitions, for spin and shape reconstruction. In addition, we are using thermal data from infrared satellites. We join both types of data in one optimisation process for modelling their spins, shape, sizes and thermal properties.
Using the Convex Inversion Thermophysical Model we recently obtained detailed models for 16 slow rotators, with the slowest one having the rotation period of as long as 59 hours. Our thermal inertia determinations provide valuable input where previously have been very few objects. Still, we cannot confirm the trend for larger thermal inertia with longer period, that if present, would allow us to study deeper layers of their surfaces. We also scaled the targets in size by fitting the shape models silhouettes to stellar occultations timings, and obtained good agreement with sizes from thermal fitting.
Our study joins a wide approach: from amateur astronomers observations to data from space observatories, and from pure lightcurve inversion to a more sophisticated simultaneous optimisation with thermal data, for a comprehensive view of these interesting targets.
Język wykładu: angielski
13 stycznia 2022
mgr Julia Pietrzak (IOA UAM)
Przewidywanie zbliżeń między obiektami satelitarnymi jest jednym z kluczowych zagadnień programu SST. Celem takich działań jest ochrona satelitów przed zderzeniami ze śmieciami kosmicznymi. Chcąc otrzymać prawidłowe wyniki trzeba jednak dobrze propagować orbitę. W tym celu wykorzystuję bibliotekę Orekit do stworzenia programu pozwalającego przewidzieć momenty zbliżeń, a także odległości na jakie zbliżą się obiekty.
Język wykładu: polski
16 grudnia 2021
prof. Krzysztof Hełminiak (CAMK PAN, Toruń)
The CREME project is a large spectroscopic survey aimed for a large number (~380) of detached eclipsing binaries (DEBs), supported by high-precision photometry, mainly from the space missions (TESS, Kepler/K2). The goal is to identify and characterise stars of rare or poorly studied classes by providing an extended set of orbital, physical, and atmospheric parameters derived with high precision. The sample contains variety of different objects (giants, low-mass stars, multiples, pulsators), many of which were studied for the first time. In my talk I will present some of the latest results, including models of targets from the TESS Guest Investigator programme, and mass estimates of 630 stars in 315 double-lined spectroscopic DEBs.
Język wykładu: angielski
9 grudnia 2021
dr Alexey Sergeyev (Observatoire de la Côte d’Azur, Nice, France)
The populations of small bodies of the Solar System (asteroids, comets, and Kuiper Belt objects) are used to constrain the origin and evolution of the Solar System. Their orbital distribution and composition distribution are both required to track the dynamical pathway from their formation regions to their current locations. We aim to increase the sample of Solar System objects (SSOs) that have multifilter photometry and compositional taxonomy. To do this we searched for moving objects in the SkyMapper Southern Survey. We used the predicted SSO positions to extract photometry and astrometry from the SkyMapper frames. Then we applied a suite of filters to clean the catalog from false-positive detections and finally we used the near-simultaneous photometry to assign a taxonomic class to objects. We release a catalog of 880,528 individual observations, consisting of 205,515 known and unique SSOs. The catalog completeness is estimated to be about 97% down to V=18 mag and the purity is higher than 95% for known SSOs. The near-simultaneous photometry provides either three, two, or a single color that we use to classify 117,356 SSOs with a scheme consistent with the widely used Bus-DeMeo taxonomy.
Język wykładu: angielski
2 grudnia 2021
prof. Anna Marciniak (IOA UAM)
Slowly rotating asteroids turn out to be abundant, yet little is known about their physical properties. In our wide campaign we observe them in a rich network of small telescopes (including amateur observatories), gathering lightcurves in the visible from multiple apparitions, for spin and shape reconstruction. In addition, we are using thermal data from infrared satellites. We join both types of data in one optimisation process for modelling their spins, shape, sizes and thermal properties.
Using the Convex Inversion Thermophysical Model we recently obtained detailed models for 16 slow rotators, with the slowest one having the rotation period of as long as 59 hours. Our thermal inertia determinations provide valuable input where previously have been very few objects. Still, we cannot confirm the trend for larger thermal inertia with longer period, that if present, would allow us to study deeper layers of their surfaces. We also scaled the targets in size by fitting the shape models silhouettes to stellar occultations timings, and obtained good agreement with sizes from thermal fitting.
Our study joins a wide approach: from amateur astronomers observations to data from space observatories, and from pure lightcurve inversion to a more sophisticated simultaneous optimisation with thermal data, for a comprehensive view of these interesting targets.
Język wykładu: angielski
Referat odwołany z powodu ograniczeń związanych z pandemią.
25 listopada 2021
dr Antti Penttilä (University of Helsinki, Finland)
We explore the performance of neural networks in automatically classifying asteroids into their taxonomic spectral classes. We particularly focus on what the methodology could offer the ESA Gaia mission. We constructed an asteroid dataset that can be limited to simulating Gaia samples. The samples were fed into a custom-designed neural network that learns how to predict the samples’ spectral classes and produces the success rate of the predictions. The performance of the neural network is also evaluated using three real preliminary Gaia asteroid spectra.
The overall results show that the neural network can identify taxonomic classes of asteroids in a robust manner. The success in classification is evaluated for spectra from the nominal 0.45–2.45 µm wavelength range used in the Bus-DeMeo taxonomy, and from a limited range of 0.45–1.05 µm following the joint wavelength range of Gaia observations and the Bus-DeMeo taxonomic system. The obtained results indicate that using neural networks to execute automated classification is an appealing solution for maintaining asteroid taxonomies, especially as the size of the available datasets grows larger with missions like Gaia.
Język wykładu: angielski
18 listopada 2021
prof. Piotr A. Dybczyński (IOA UAM)
Mamy coraz dokładniejsze dane o gwiazdach z otoczenia Słońca ale nadal precyzyjne odtworzenie parametrów ich zbliżenia do Układu Słonecznego jest w wielu przypadkach trudne. Powoduje to, że oszacowanie wpływu takich przejść gwiazdowych np. na komety długookresowe jest skomplikowane lub wręcz niemożliwe w obecnej chwili.
Język wykładu: polski
4 listopada 2021
mgr Jacek Haponiak (IOA UAM)
Model bąka Colmbo opisuje dynamikę obrotową bryły sztywnej, obiegającej punkt materialny, pod wpływem siły grawitacji. Zmienne typu kąt-działanie w mechanice klasycznej to zestaw zmiennych kanonicznych użytecznych w rozwiązywaniu wielu układów całkowalnych. W trakcie prezentacji zostaną przedstawione zmienne kąt-działanie dla modelu bąka Colombo.
Język wykładu: polski
28 października 2021
mgr Hanna Klimczak (IOA UAM, Politechnika Poznańska)
The aim of the project is the classification of asteroids according to the most commonly used asteroid taxonomy (Bus-Demeo et al. 2009) with the use of various machine learning methods like Logistic Regression, Naive Bayes, Support Vector Machines, Gradient Boosting and Multilayer Perceptrons. Different parameter sets are used for classification in order to compare the quality of prediction with limited amount of data, namely the difference in performance between using the 0.45mu to 2.45mu spectral range and multiple spectral features, as well as performing the Prinicpal Component Analysis to reduce the dimensions of the spectral data.
Język wykładu: angielski
21 października 2021
mgr Volodymyr Troianskyi (IOA UAM)
The Lucy mission consists of five flybys of Trojan asteroids to investigate the differences in surface and internal properties across the population of Trojan asteroids. From these five encounters we will be able to observe seven Trojan asteroids: (3548) Eurybates and its small satellite Queta, (15094) Polymele, (11351) Leucus, (21900) Orus, (617) Patroclus, and Meneotius.
We make photometric observations of these targets to confirm the taxonomy of asteroids, rotational periods and creating phase curves.
Język wykładu: angielski
14 października 2021
prof. Tomasz Kwiatkowski, mgr Paweł Koleńczuk (IOA UAM)
Very Small Asteroids (objects with diameters smaller than about 150 m) can be spun-up by the YORP effect to rotation periods as short as tens of seconds. It is also hypothesised, that in the same process their spin axes are asymptotically drawn to the position perpendicular to the orbital plane. So far this effect has been observed only for one VSA and needs further verification. In this talk results of an observing campaign of 2021 DW1, shall be presented. During 6 days in March 2021 this object swept a 170 degrees long arc on the sky which made it an excellent target for physical characterisation, including spin axis and shape derivation.
Język wykładu: angielski
W roku akademickim 2020/2021 wystąpili:
17 czerwca 2021
Marco Micheli (NEO Coordination Centre, ESA)
ESA’s NEO Coordination Centre, established 8 years ago in Frascati,near Rome, is one of the components of ESA’s Planetary Defence Programme.
Among the tasks of the Programme and the Centre is the collection of astronomical observations of NEOs, with a specific focus on asteroids presenting a non-zero impact threat to our planet. The observational activities of the Programme are divided into various tasks. Among them are:
– The development of a dedicated NEO survey telescope, the so-called “Flyeye”, soon to be installed in Southern Italy, plus two other mixed-use wide-field telescopes in Spain and Chile.
– The collection of high-precision astrometric observations of possible impactors, with various facilities worldwide (including a dedicated program with ESO’s VLT).
– The establishment of a worldwide network of telescopes, with global latitudinal and longitudinal coverage, capable of ensuring quick-reaction observational capabilities in case of upcoming impact
threats (the so-called “imminent impactors”)
– The development of resources and capabilities for archival searches and precoveries.
In this talk we will discuss the importance of NEO observations for the mitigation of the asteroidal impact threats, and present some of the key observational results of our Programme.
10 czerwca 2021
prof. Tadeusz Jopek (IOA UAM)
W pierwszej części wystąpienia, zaprezentowane zostaną dwa sposoby generowania syntetycznych (sztucznych) orbit małych ciał.
W skrócie, omówimy:
1) metodę wielowymiarowego estymatora jądrowego funkcji gęstości prawdopodobieństwa,
2) metodę odwracania dystrybuanty.
W części drugiej, wykorzystując dostępną próbę orbit małych ciał, porównamy własności syntetycznych orbit otrzymanych za pomocą każdej z metod.
27 maja 2021
Karolina Dziadura (IOA UAM)
The orbital motion of small bodies is affected by the Yarkovsky effect. First-time the effect was proposed by Yarkovsky in 1901 and then popularized by Öpik in the 1950s. However, the first direct detection was only made in 2003 thanks to radar observations. Nowadays there are over hundred detections for NEAs and only a few for Main-Belt objects.
The main goal of this study is to improve an asteroid orbit using GAIA DR2 astrometry. It was claimed that the Gaia mission will improve asteroids orbits and to find new Yarkovsky detections thanks to the high precision and accuracy of its astrometry. I converted all of the available data to ADES format and then used it to orbit determination. I used OrbFit software which is a Fortran program for orbit propagation, ephemerides computation, orbit determination, close approach analysis, and impact monitoring. I will show results for 42 asteroids, where for 21 of them I obtained an A2 parameter with signal to noise ratio greater than 3.
20 maja 2021
Lukas Shrbeny (Czech Academy of Science)
This talk should provide brief introduction into observation of fireballs, their sources, and basic physical properties that can be determined from observations and modeling.
13 maja 2021
prof. Michał Michałowski, dr Krzysztof Kamiński (IOA UAM)
Gamma-ray bursts (GRBs) are explosions of the most massive stars. The detection of even a single GRB exploding in the very early Universe is important because it allows us to constrain the star-formation activity and the conditions necessary for such stars to be formed. We will show that a recent extraordinary discovery of a GRB at a redshift of 11 (only 420 million years after the Big Bang) was in fact due to a signal from a man-made satellite BREEZE-M DEB (TANK), a debris from a Proton rocket.
6 maja 2021
Emil Wilawer (IOA UAM)
The number of sparse asteroid photometry being gathered by both space and ground-based surveys is growing exponentially. This big volume of data poses a computational challenge both due to large amount of data to be processed as well as new methods needed to combine data from various sources (e.g. obtained by different techniques, in different filters, having different random and systematic errors). I will present a novel approach to obtain asteroid phase curves combing sparse Gaia DR2 photometry and differential ground-based photometry, that in the traditional approach cannot be used for phase-curves. Combining those two data types allows for extraction of phase-curve information for growing number of objects. The main goal is to develop algorithm capable of merging sparse and dense data sets both relative and differential in preparation for asteroid observations originating for example from the Gaia, TESS, ATLAS, LSST, K2, VISTA and many others.
29 kwietnia 2021
Volodymyr Troianskyi (IOA UAM)
Since July 2014, the ESA Gaia mission has been surveying the entire sky down to magnitude 20.7 in the visible. In addition to the millions of stars, thousands of Solar System Objects (SSOs) are observed daily. By comparing their positions to those of known objects, a daily processing pipeline filters known objects from potential discoveries. However, owing to Gaia’s specific scanning law designed for stars, potential newly discovered moving objects are characterized by very few observations, acquired over a limited time. This aspect was recognized early in the design of the Gaia data processing. A daily processing pipeline dedicated to these candidate discoveries was set up to release calls for observations to a network of ground-based telescopes. Their aim is to acquire follow-up astrometry and to characterize these objects. From the astrometry measured by Gaia, preliminary orbital solutions are determined, allowing to predict the position of these potentially new discovered objects in the sky accounting for the large parallax between Gaia and the Earth (separated by 0.01 au). A specific task within the Gaia Consortium has been responsible for the distribution of requests for follow-up observations of potential Gaia SSO discoveries. Since late 2016, these calls for observations (called alerts) are published daily via a Web interface, freely available to anyone world-wide. Between November 2016 and July 2020, over 1700 alerts have been published, leading to the successful recovery of more than 200 objects. Among those, six have provisional designation assigned with the Gaia observations, the others being previously known objects with poorly characterized orbits, precluding identification at the time of Gaia observations. There is a clear trend for objects with a high inclination to be unidentified, revealing a clear bias in the current census of SSOs against high inclination populations.
15 kwietnia 2021
dr Krzysztof Kamiński (IOA UAM)
Obserwatorium Astronomiczne Uniwersytetu im. A. Mickiewicza w konsorcjum z Uniwersytetem w Zurychu, firmą ITTI z Poznania i firmą 6ROADS z Krakowa (liderem konsorcjum) realizowało w latach 2019-2021 projekt Europejskiej Agencji kosmicznej o akronimie SPACE STONES (ang.Space Surveillance and Tracking in Observational Network with Event-based Sensors). W ramach tego projektu przeprowadzono testy laboratoryjne oraz obserwacyjne w celu sprawdzenia przydatności kamer dynamicznych (ang. DVS – Dynamic Vision Sensor lub EBS – Event Based Sensor) do obserwacji sztucznych satelitów Ziemi. Opracowano metody dokładnej rejestracji czasu zmian rejestrowanych przez kamery dynamiczne, wytworzono oprogramowanie do transformacji asynchronicznego strumienia danych do formatu FITS, opracowano metody wykonywania oraz analizy astrometrycznej danych z tych kamer. Wykonano pierwsze na świecie (zgodnie z naszą wiedzą) pomiary astrometryczne satelitów nawigacyjnych tego typu kamerą oraz pomiary jej zasięgu, dokładności oraz opóźnień w rejestracji zmian.
8 kwietnia 2021
Irina Belskaya (Karazin Kharkiv National University)
Polarimetry is an effective remote sensing tool for studying surfaces of atmosphereless small Solar system bodies, in particular, for assessing surface albedo and texture. Last decade the interest to polarimetric investigations has been increased first of all thanks to the progress in instrumentation. The achievements and problems of using polarimetry for studying surfaces of atmosphereless small Solar system bodies from near-Earth asteroids to transneptunian objects will be discussed.
25 marca 2021
prof. Tomasz Kwiatkowski (IOA UAM)
SANORDA is an acronym for Service for Archival NEO Orbital and Rotational Data Analysis. It has been developed by our Institute under a contract from ESA. SANORDA is web based and consists of four modules: NHOD (for analysing the influence of the number of astrometric observations of newly discovered NEOs on the accuracy of the orbits computed for them), NLCD (for storing and visualising asteroid lightcurves), NPDT (for computing asteroid rotation periods from their lightcurves), and NPAT (for fitting phase functions to the asteroid magnitude-phase relations). In the talk, several use cases of SANORDA, which can be of interest to asteroid researchers, will be presented.
18 marca 2021
dr Edyta Podlewska-Gaca (IOA UAM)
Dzisiejsze seminarium będzie o współpracy astronoma z lekarzem okulistą i o tym jak doszło do stworzenia klasyfikacji ostrego uszkodzenia plamki żółtej w wyniku patrzenia na słońce bez ochrony.
11 marca 2021
dr Edyta Podlewska-Gaca (IOA UAM)
Satelita Kepler jest bardzo użytecznym narzędziem stworzonym do badań różnego typu zjawisk we Wszechświecie np. pulsacje gwiazdowe, tranzyty egzoplanet czy zjawiska mikrosoczewkowania grawitacyjnego. Jednak Kepler daje także możliwość śledzenia małych ciał Układu Słonecznego przechodzących akurat w jego polu widzenia. W prezentacji przedstawię wyniki otrzymane z Kampanii K2C9, które umożliwiły wyznaczenie po raz pierwszy okresów rotacji dla dużej grupy planetoid. Omówię, także kilka ciekawych obiektów, które są interesującym materiałem do dalszych badań.
11 lutego 2021
Steve Schulze (Stockholm University)
The paradigm shift from galaxy-selected to quasi-synoptic surveys led to a revolution in the study of optical transients. The Palomar Transient Factory (PTF) has played an important role in this revolution. PTF was a fully-automated, wide-field survey using the 1.2-m Samuel Oschin telescope (P48) at Palomar Observatory (USA). Between 2009 and 2017, PTF discovered almost 900 core-collapse supernovae. Here, I present the host galaxy properties of the core-collapse supernova sample. I obtained photometry from the rest-frame UV to the NIR for each host and modelled the spectral energy distributions to extract the mass and star-formation rate of each host. I will contrast each sub-class’s ensemble properties with expectations from field-galaxy samples to deduce whether different classes of core-collapse supernovae show a preference for particular galactic environments. Furthermore, I will show how we can use SNe as beacons to study extreme star-formation environments and how we can use them to select rare phases in galaxy evolution.
4 lutego 2021
prof. Tadeusz Jopek (IOA UAM)
Rankiem 29 Stycznia 2021 o godz. 6:04:54-58 UTC z różnych miejsc w Czechach i Polsce zaobserwowano jasny bolid. Z powodu złej pogody jego przelot nie został zarejestrowany przez sieć profesjonalnych kamer meteorowych. Znalazł się on jednak na nagraniach z amatorskich kamer, które można odnaleźć w internecie. Jeśli zostaną one prawidłowo skalibrowane astrometrycznie, można je będzie wykorzystać do wyznaczenia trajektorii bolidu.
Dwa materiały video pochodzą z terenu Polski. Jeden film został nagrany z samochodu stojącego w miejscu w pobliżu Poznania. Drugi film został zarejestrowany z samochodu jadącego drogą w pobliżu miejscowości Świebodzin (okolice Zielonej Góry). Oba materiały są kluczowe w wyznaczeniu punktu spadku potencjalnych meteorytów.
W czasie krótkiej prezentacji przedstawię metody kalibracji zdjęć przelotu bolidu. Wolontariusze do wykonania tego zadania są mile widziani.
28 stycznia 2021
mgr Monika Kamińska (IOA UAM)
Rosnąca populacja obiektów krążących wokół Ziemi wymaga stałego monitoringu, dzięki któremu możliwe jest przewidywanie potencjalnych kolizji funkcjonujących satelitów z innymi, nieaktywnymi obiektami. Monitoring taki jest prowadzony najczęściej za pomocą radarów i obserwacji optycznych. Obserwacje satelitów przy pomocy teleskopów optycznych są wymagające, m.in. ze względu na zróżnicowanie jasności obserwowanych obiektów i prędkości kątowe sięgające w skrajnych przypadkach nawet kilku stopni na sekundę. W prezentacji omówiony zostanie projekt ESA “OGS Camera Requirements and Benchmarking”, w ramach którego przygotowywana jest kompleksowa modernizacja kamery do optycznych obserwacji sztucznych satelitów Ziemi na teleskopie ESA Optical Groung Station (OGS) na Teneryfie. W ramach tego projektu OA UAM w konsorcjum z firmą 6ROADS prowadzi analizy teoretyczne oraz testy praktyczne najnowszych cyfrowych kamer astronomicznych dostępnych na rynku w celu wskazania najkorzystniejszego modelu, który ma zastąpić dotychczas stosowaną kamerę CCD.
Język wykładu: angielski
21 stycznia 2021
dr Magdalena Polińska (IOA UAM)
Planetoidy to skaliste pozostałości z czasów powstania Układu Słonecznego. Badając małe ciała, możemy dowiedzieć się więcej o powstawaniu i ewolucji naszego Układu Planetarnego. Znamy już 420 planetoid podwójnych. Istnieje kilka typów systemów podwójnych. Szczególnym ich przypadkiem są układy z dwoma ciałami o podobnej wielkości i okresem rotacji obu składników równym okresowi orbitalnemu – nazywane są one synchronicznymi planetoidami podwójnymi. Obserwowanie i modelowanie takich obiektów to jeden z kilku możliwych sposobów uzyskania informacji o wartościach masy i rozmiarów ciał, a następnie obliczenie ich gęstości. Podczas wystąpienia chciałbym przedstawić aktualne dane i wyniki dla tej interesującej grupy planetek podwójnych.
14 stycznia 2021
prof. UAM dr hab. Michał Michałowski (IOA UAM)
The way galaxies stop forming new stars (quenching) is a key aspect of galaxy evolution. This is connected with removal of gas, the fuel of star formation. I will review what we know about the mechanism of the removal of interstellar medium (ISM) from galaxies and how fast this process is. I will then present an alternative way to study the ISM removal by selecting dusty early-type galaxies, for which the decrease of gas and dust can be tracked as a function of age. This led to the first direct measurement of the ISM removal timescale and to the conclusion that the cold ISM is likely removed by feedback from old stellar populations.
17 grudnia 2020
Tomas Kohout (Helsinki University)
Shock induced changes in ordinary chondrite meteorites related to impacts or planetary collisions are known to be capable of altering their optical properties. Thus, one can hypothesize that a significant portion of the ordinary chondrite material may be hidden within the observed dark C/X asteroid population. The exact pressure-temperature conditions of the shock-induced darkening are not well constrained. Thus, we experimentally investigate the gradual changes in the chondrite material optical properties as a function of the shock pressure.
10 grudnia 2020
mgr Aleksandra Leśniewska (IOA UAM)
There exists two classes of gamma ray bursts (GRBs), which are distinguished by the duration of the prompt high-energy emission. Long GRBs, with durations larger than 2 s, are firmly associated with the explosions of massive stars, although in three instances, luminous supernovae (SNe) have not been detected, despite deep observations. The nature of these bursts is unclear. Our aim is to establish the properties of the interstellar medium (ISM) of the host galaxy of one of these events, GRB 111005A, in order to shed light on the nature of these peculiar objects. We used new HI line measurements and previously published optical integral field spectroscopy in order to analyze the environment in which the GRB was located. We studied the distribution of the host properties e.g. atomic gas mass, star formation rate (SFR), and kinematics.
3 grudnia 2020
mgr Paweł Koleńczuk (IOA UAM)
W wystąpieniu przedstawię wyniki obserwacji i analizy fotometrycznej bardzo małej planetoidy bliskiej Ziemi 2020 UA. Obiekt zaobserwowano 20 października 2020r., 0.7-m teleskopem RBT. Przedstawione wyniki będą dotyczyć własności fizycznych planetoidy takich jak: okres rotacji, jasność absolutna, wielkość i typ taksonomiczny.
26 listopada 2020
prof. UAM dr hab. Przemysław Bartczak (IOA UAM)
W ostatnich latach wzrosło wykorzystanie klastrów obliczeniowych w badaniach prowadzonych w IOA UAM. Niektóre zagadnienia naukowe nie są realizowane z powodu ograniczeń w dostępie do profesjonalnych systemów obliczeniowych. W prezentacji przedstawiona zostanie platforma BOINC oparta na zasobach komputerowych wolontariuszy, która sprawdza się w realizacji wielkich wyzwań obliczeniowych od wielu lat.
19 listopada 2020
dr Anna Łosiak (University of Exeter, UK)
Recognising small terrestrial impact craters developed in unconsolidated materials is a problem (French and Koeberl 2010). In such cases, impact cratering indicators, established based on larger structures formed in consolidated materials, are not useful: there are no shatter-cones and the amount of shocked quartz produced during the impact is very small and spread out over a large area. For example, in the Morasko strewn field (the largest structure is ~100 m in diameter), the volume of sediment shocked above 5 GPa (required for producing planar deformation features in quartz) is negligible (Bronikowska et al. 2017); extensive hunt for shocked grains remained unsuccessful (personal communication: A. Muszynski, A. Losiak). Because of that the main (and in most cases the only) recognition criterium applied for the small impact craters in unconsolidated materials is recognition of the preserved meteorite fragments associated spatially with the crater.
During the the seminal I will present results of my research on this topic performed as part of my Marie Skłodowska Curie Individual Fellowship at the at the University of Exeter.
12 listopada 2020
dr Krzysztof Kamiński (IOA UAM)
W ostatnich latach znacznie wzrosło zainteresowanie optycznymi obserwacjami sztucznych satelitów Ziemi prowadzonymi podczas dnia. W prezentacji omówione zostaną najważniejsze wyzwania związane z tego typu obserwacjami, dotychczasowe osiągnięcia w tej dziedzinie oraz plany wykorzystania zespołu teleskopów PST3 do przeprowadzenia eksperymentalnych obserwacji dziennych.
5 listopada 2020
dr Dagmara Oszkiewicz (IOA UAM)
Characterisation of the V-type asteroid population may help to comprehend the planetesimal formation and evolution. Asteroid phase-curves are known to relate to surface properties such as asteroid taxonomy, surface roughness, particle size distribution, albedo and many others, providing insight into surface properties of the V-types.
Gil-Hutton et al. (2017) showed that the basaltic asteroids display two distinct polarimetric behaviors, which they attributed to the regolith particle size, however mineralogical differences can not be excluded. Considering that phase-curve parameters relate to surface and regolith properties, they may verify those distinct behaviors.
We observed about 20 asteroids during around 250 nights (over 500 fragmental lightcurves) to obtain high quality phase curves. We fitted the standard H,G; H,G1,G2, and H, G12 phase functions, limiting them to physical solutions only. This greatly extends the sample of well determined phase-curves for the underrepresented V-types. For asteroids with data from multiple oppositions we used a simultaneous fit assuming the same slope parameters in all apparitions and different absolute magnitude values. From these data we also derived the G12* parameter to be used in single parameter phase functions recommended for fitting low quality photometry. We do not find substantial evidence for any clustering into distinct phase curve parameters groups as suggested by Gil-Hutton et al. 2017. Only one asteroid (2763 Jeans) shows an exceptionally high G2 value.
Further work should be conducted to determine slope parameters of more V-types to further verify the division of V-type asteroids into two distinct groups. Obtaining phase curves of non-Vestoids (such as those in the mid and outer Main Belt) may also help clarify if the division into distinct V-type groups is due to particle size or mineralogical differences.
29 października 2020
prof. Piotr A. Dybczyński (IOA UAM)
Całkowanie numeryczne ruchu komet długookresowych dla zbadania ich przeszłości i przyszłości w ich poprzednim i następnym obiegu orbitalnym wymaga uwzględnienia perturbacji od potencjału Galaktyki i oddziaływania gwiazd przechodzących blisko Słońca. W sytuacji gdy po opublikowania katalogu Gaia DR2 takich gwiazd mamy około 650 i chcemy uwzględniając nie tylko ich oddziaływanie na kometę ale również na Słońce i na siebie nawzajem zagadnienie robi się obliczeniowo bardzo trudne. Dodatkowo, ponieważ opis ruchu mamy w układzie Galaktocentrycznym więc napotykamy na znaczne numeryczne ograniczenia dokładności gdy kometa jest blisko Słońca. Pokażemy jak uporać się z tymi i innymi trudnościami.
22 października 2020
dr hab. Łukasz Wyrzykowski (OA UW)
Black holes (BH) are everywhere, there should be hundreds of millions of stellar-origin black holes in our Milky Way Galaxy. However, we only know about 50 or so cases, mostly from X-ray binaries, where a BH accretes matter from its stellar companion, or from binary system involving a star and a BH. Single black holes, even if nearby, are essentially black and invisible.
Gravitational microlensing offers an opportunity to discover black hole and other dark objects just by the fact they are massive and bend the background light. There have been thousands of microlensing events discovered by OGLE, Gaia, ZTF and other projects. However, in order to uniquely recognise a black hole lens and distinguish from a regular stellar lens, it is required to measure the size of the Einstein Radius as well as the distances of both lens and the source. Gaia space mission’s astrometric data will allow measuring Einstein radii for all events, however, without a dense photometric coverage of their light curves, the parallax effect willnot be measurable.
The Time-Domain work package of the EC’s Horizon 2020 OPTICON grant has been established in order to coordinate global long-term time-domain observations, such as of candidates for lensing black holes. In years 2021-2024, these actions will be extended also to radio time-domain observations, within the new Horizon 2020 grant OPTICON-RadioNET PILOT (ORP). In my talk, I will describe the current state of the black hole microlensing searches and will present the results obtained so far with the OPTICON Time-domain telescope network.
15 października 2020
mgr Jakub Tokarek (IOA UAM)
W budynku Obserwatorium Astronomicznego w Poznaniu znajduje się trudna do zliczenia ilość wszelkiej maści dokumentów i materiałów historycznych. Niektóre z nich są starsze niż sam Uniwersytet Poznański (założony w 1919 roku). W ciągu ostatnich kilku miesięcy udało się zebrać i uporządkować materiały pochodzące z okresu Drugiej Wojny Światowej, kiedy to działało “Universitäts – Sternwarte Posen”. Katalog archiwum liczy obecnie ponad 650 pozycji, począwszy od drobnych rachunków, poprzez korespondencję pracowników Obserwatorium, a skończywszy na sprawozdaniach rocznych. Wszystkie one w różnym stopniu poszerzają wiedzę nie tylko na temat funkcjonowania Obserwatorium, ale także całego Reichsuniversität Posen, współpracy z innymi ośrodkami nauki w Europie, a nawet daje wgląd w codzienne funkcjonowanie różnych fragmentów nazistowskiej III Rzeszy.
W roku akademickim 2019/2020 wystąpili:
25 czerwca 2020
dr Krzysztof Kamiński, mgr Monika Kamińska (IOA)
Obserwowany ostatnio wzrost liczby sztucznych satelitów oraz śmieci kosmicznych stanowi rosnące utrudnienie dla obserwacji astronomicznych. Kilku autorów opublikowało analizy tego problemu, stawiając pytanie o przyszłość obserwacji astronomicznych, szczególnie w przypadku przeglądów z dużym polem widzenia oraz długich czasów naświetlania. W celu zbadania problemu stworzyliśmy zupełnie nowy serwis www, zaprojektowany specjalnie do przewidywania przelotów satelitów oraz szacowania ich jasności na wybranych obszarach nieba. Jest to pierwsze publicznie dostępne narzędzie umożliwiające oszacowanie stosunku sygnału do szumu śladu satelitarnego na zdjęciach dla wszystkich satelitów z publicznie dostępnymi orbitami. Zaprezentujemy zastosowaną metodologię oraz przykłady użycia bazujące na realnych zdjęciach wykonanych z kilku różnych teleskopów.
18 czerwca 2020
mgr Karolina Dziadura (IOA)
The orbital motion of small bodies is affected by the Yarkovsky effect. First-time the effect was proposed by Yarkovsky in 1901 and then popularized by Öpik in 1950s. However, the first direct detection was only made in 2003 using radar observations. Nowadays there are hundreds of detections for NEAs and only a few for Main-Belt objects. In this work, I attempt to detect the Yarkovsky effect among multiple Main-Belt objects and other asteroids. I will show preliminary results for five asteroids using the OrbFit software. OrbFit is a Fortran program for orbit propagation, ephemerides computation, orbit determination, close approach analysis, and impact monitoring. Orbits were calculated using FitObs with and without the Yarkovsky effect. Next, the ephemeris were computed for the times of GAIA observations and compared with the GAIA DR2 data.
4 czerwca 2020
mgr Julia Matysiak (IOA)
„Orekit”- pod taką nazwą funkcjonuje biblioteka zawierająca elementy pozwalające na wykonywanie obliczeń orbitalnych głównie w zakresie dynamiki sztucznych satelitów Ziemi. Wykorzystywana jest przez wiele organizacji np. CNES (Centre National d’Études Spatiales), ESA (European Space Agency), U.S. Naval Research Laboratory. Z roku na rok coraz więcej osób rozpoczyna swoją przygodę z wykorzystaniem „Orekita” do celów naukowych. Próbując wykorzystać bibliotekę do obliczeń orbitalnych staram się odpowiedzieć na pytania jak duży jest potencjał tej biblioteki oraz do jakich celów można jej użyć.
28 maja 2020
prof. Wojciech Dimitrow (IOA)
Układ V2080 Cyg to para zaćmieniowa gwiazd. Dotychczasowe badania innych zespołów wskazują, że są to gwiazdy o zbliżonych masach i rozmiarach oraz że w widmach obiektu obecny jest ślad trzeciego składnika. W naszym Obserwatorium zorganizowano kampanię obserwacyjną obiektu. Zgromadzono dane spektroskopowe z dwóch instrumentów: pierwszy z nich to 1.88m teleskop Cassegraina David Dunlap Observatory. Drugi instrument to PST1 wyposażony w spektrograf typu Echelle. Duża liczba obserwacji o bardzo dobrej jakości pozwoliła na dokładne wyznaczenie mas składników pary zaćmieniowej. Dodatkowo przeanalizowano dane ruchów własnych oraz paralaks z misji GAIA DR2. Wskazują one na to, iż wizualni towarzysze obiektu nie są z nim związani dynamicznie, tylko są gwiazdami tła.
21 maja 2020
prof. Przemysław Bartczak (IOA)
Zaprezentuje adaptacje metody SAGE umożliwiającą modelowanie parametrów fizycznych planetoid na podstawie obserwacji fotometrycznych i obrazów uzyskanych za pomocą optyki adaptacyjnej.
14 maja 2020
mgr Ewa Śreniawska (IOA)
Delta Ceti jest jedną z najjaśniejszych i najdłużej badanych gwiazd zmiennych pulsujących typu beta Cephei. Początki obserwacji sięgają pierwszych lat XX wieku. Gwiazda wykazywała systematyczny wzrost okresu głównej pulsacji. Kolejne dane podważyły jednak ten wynik, pokazując, że rosnący trend zaczął się załamywać. Pojawiła się również hipoteza o wielomodalności delta Ceti. Dotychczasowa analiza koncentrowała się głównie na obserwacjach fotometrycznych, natomiast obserwacje spektroskopowe były słabej jakości.
W latach 2014-2018 została przeprowadzona kampania spektroskopowa z wykorzystaniem teleskopów systemu GATS (Global Astrophysical Telescope System). Zostały zgromadzone 1022 widma wysokiej rozdzielczości, które stanowią największy jednorodny zbiór danych spektroskopowych dla tej gwiazdy. Analiza wykazała, że zmiany okresu pulsacji mają bardziej złożony charakter, niż wskazywały wcześniejsze dane. Nie udało się również znaleźć żadnych dodatkowych modów pulsacji.
Uzyskane wyniki pozwalają nam postawić hipotezę, że tak skomplikowana zmienność może wynikać z obecności jednego lub więcej niewidocznych obiektów krążących wokół gwiazdy.
7 maja 2020
prof. dr hab. Sławomir Breiter (IOA)
Na ruch obrotowy małych ciał działają efekt YORP i nieelastyczne deformacje rozpraszające energie. Według modelu teoretycznego (S. Breiter i M. Murawiecka) efekt YORP wzbudza nutację silniej niż rozpraszanie energii ją tłumi. A to kłóci się ze statystyką obserwacji.
30 kwietnia 2020
mgr Magda Butkiewicz-Bąk (IOA)
Teoria ewolucji Układu Słonecznego mówi, że planetoidy są pozostałościami po formowaniu się jego wewnętrznych obszarów. Główny pas planetoid, pas Kuipera oraz pył obecny w Układzie Słonecznym stanowią analogię do odległych
układów pozasłonecznych, w których obserwuje się tzw. dyski odłamkowe. Obiekty te mogą nieść informacje na temat procesów, jakie zachodziły w dysku protoplanetarnym, o tym jak przebiegała ich ewolucja. Ważną rolę w tym procesie odgrywają planetoidy. Podczas swojego wystąpienia zaprezentuję wyniki badań Bardzo Małych Planetoid uzyskane w ramach pracy doktorskiej.
23 kwietnia 2020
dr hab. Anna Marciniak (IOA)
Obserwacje zjawisk zakryciowych są bardzo efektywną metodą badania małych ciał Układu Słonecznego. Pozwalają wyznaczać ich rozmiary, kształty, odkrywać ich satelity a nawet pierścienie. Dla dużych obiektów transneptunowych technika ta umożliwia także wyznaczanie gęstości tych ciał.
Obserwacje takie są stosunkowo proste – wystarczy dokładnie określić dwa momenty czasu: zniknięcia i ponownego pojawienia się gwiazdy za zakrywającym ją ciałem. Najważniejsze jednak, by te obserwacje były skoordynowanymi kampaniami. Uzyskuje się wtedy wiele cięciw okultacyjnych, zwiększając precyzję wyznaczonych parametrów. Omówione zostaną pozytywne obserwacje zakryciowe jakie wykonano niedawno w naszym obserwatorium.
16 kwietnia 2020
mgr Łukasz Tychoniec (Leiden University)
I will present an overview of observational efforts to study protostellar systems with ALMA in order to understand the conditions in which planets start to form. I will also describe the scientific plan of the JWST/MIRI European Consortium to observe star-forming regions.
9 kwietnia 2020
dr Dagmara Oszkiewicz (IOA)
SONATA13 is an NCN funded project aimed at verifying the Bottke et al. (2006) planetesimal formation and evolution scenario. According to that research planetesimals formed close to the Sun, in the terrestrial planet region and then scattered into the main asteroid belt. The remains of those planetesimals (so called V-type asteroids) can be observed in the current main belt. Derivation of spin statistics of those asteroids will help verify the Bottke et al. (2006) theory. In this presentation I will discuss the progress of the project and the preliminary results.
2 kwietnia 2020
prof. Edwin Wnuk (IOA)
Głównym zadaniem SST (Space Surveillance and Tracking) jest detekcja i śledzenie obiektów satelitarnych w przestrzeni wokółziemskiej. Zebrane przez systemy SST informacje i utworzone katalogi orbit są podstawą do przygotowania analiz w zakresie trzech tzw. serwisów SST:
• Collision Avoidance (CA) – przewidywania zbliżeń i kolizji między obiektami,
• Re-entry Analysis (RE) – przewidywania momentów czasu i miejsca wejścia obiektu w do atmosfery i ewentualnego spadku na powierzchnię Ziemi,
• Fragmentation Analysis (FR) – detekcja i monitorowanie obiektów powstałych w trakcie fragmentacji macierzystych obiektów na orbicie wokółziemskiej.
W referacie zostaną przedstawione różne zagadnienia teoretyczne i obliczeniowe związane z dwoma z powyższych serwisów: RE i FR.
26 marca 2020
mgr Dorota Krużyńska, mgr inż. Mikołaj Krużyński (IAO)
“End-to-End-Procedure for satellite Orbit Catalogue from optical observation (E2EPOC)” to projekt ESA, którego jednym z wykonawców jest OA UAM. Głównym celem projektu jest zaprojektowanie i weryfikacja procedur niezbędnych dla działania polskiego systemu SST. W szczególności tworzenia i utrzymania katalogu orbitalnego na podstawie własnych obserwacji. Procedury te muszą być odpowiednio zaprojektowane – począwszy od wyboru obiektów satelitarnych, poprzez planowanie obserwacji, wykonanie obserwacji, wyznaczenie orbity, aż po aktualizację ich orbity w katalogu. W niniejszej prezentacji zostaną omówione cele projektu, sposób ich realizacji i uzyskane wyniki. W szczególności skupimy się na procedurach i narzędziach wykorzystywanych w procesie wyznaczania orbit i budowania katalogu.
19 marca 2020
dr Edyta Podlewska-Gaca (IOA)
Thanks to adaptive optics imaging we are able to obtain high resolution images of asteroids and get new insight into their nature. I will present the results of such studies on VLT/SPHERE telescope. In particular it will be described how Hygiea became a candidate for a dwarf planet, and why Pallas looks like a golf ball.
12 marca 2020
Omawienie bieżących spraw
5 marca 2020
Otwarte spotkanie ze studentami poświęcone kierunkowi astronomia
27 lutego 2020
prof. Jean Surdej (University of Liège)
Magnificent phenomena do not only take place in the Universe (gravitational lensing) but also under the tree foliages which surround us. A short introduction to apprehend these nice phenomena will be given. We shall also report on a recent systematic search for multiply imaged quasars based upon observations carried out with Gaia.
30 stycznia 2020
dr Radosław Poleski (Obserwatorium Astronomiczne UW)
Full understanding of planet formation and evolution cannot be achieved without finding exoplanetary analogs of planets observed in Solar System. In particular, analogs of Uranus and Neptune are hard to find due to their long periods and low luminosities. The origin of Uranus and Neptune cannot be explained using standard models of planet formation and ice giant exoplanets can shed light on formation of the widest-orbit planets. I will present currently known ice giant exoplanets and their connection to widely-discussed free-floating planets. I will also discuss possible future studies with NASA and ESA flagship missions: WFIRST and Euclid.
23 stycznia 2020
prof. Agnieszka Kryszczyńska (IOA)
(60558) Echeclus was discovered in 2000 by Marsden and classied as a Centaur object. Surprisingly it presented several ourbursts: the largest ever observed for Centaurs in December 2005, and the smaller ones in May 2011 and in August 2016. On the pre-discovery archive images a cometary activity was also visible — that is why this object got also a cometary designation: 174P/Echeclus.
Lightcurves obtained between the outbursts did not show any cometary activity even during perihelion passage in April 2015, so they may serve as an input data for spin vector and shape modelling. For this purpose photometric data should cover different observing geometries. Collecting them for Echeclus is a long-lasting process because its long orbital period.
Combining all available lightcurves covering a 20 year observing period with three new lightcurves obtained in December 2019 at our RBT robotic telescope in Arizona, allowed us to determine the spin axis and shape model for this object. For that we used the SAGE technique developed by P. Bartczak from our Institute. Our model seems to be the first one obtained for a centaur based on only photomteric data.
9 stycznia 2020
prof. Piotr A. Dybczyński (IOA)
Nasze oprogramowanie i zestawy danych gwiazdowych pozwoliły na poszukanie potencjalnego źródła międzygwiazdowej komety 2I/Borisov wśród gwiazd zbliżających się do Słońca. Wydawało się, że układ podwójny Kruger 60 najlepiej nadaje się na potencjalne miejsce pochodzenia tego obiektu, brakowało jedynie dokładnych danych o prędkości radialnej jego składników. Otrzymana w wyniku prywatnej korespondencji nowa wartość prędkości radialnej środka masy układu Kruger 60 wykluczyła taką możliwość. Przedstawione zostaną metody takich poszukiwań i problem “publikowalności” takich wyników.
Więcej:
https://arxiv.org/abs/1909.10952.
19 grudnia 2019
mgr Paweł Koleńczuk (IOA)
Fotometria Planetoid Bliskich Ziemi boryka się z problemem ich obserwowanej dużej prędkości na niebie podczas zbliżania się do Ziemi, co powoduje rozciąganie obrazu planetoidy i/lub gwiazd na ramce CCD (powstają wtedy wydłużone ślady). Klasyczna fotometria różnicowa z użyciem okrągłych apertur nie daje w takiej sytuacji dobrych rezultatów. Rozwiązaniem jest apertura pigułkowa, która idealnie odzwierciedla kształt śladów. W rezultacie, zachowujemy optymalny stosunek sygnału do szumu. Kształt apertury może być opisany jako dwa półokręgi połączone prostokątem. Zastosowanie apertury pigułkowej nie ogranicza się do fotometrii planetoid. Problem obserwowanej dużej prędkości na niebie dotyczy również sztucznych satelitów Ziemi. Apertura pigułkowa może również wyeliminować problem fotometrii gwiazd podczas nieoczekiwanego ruchu teleskopu, np. w trakcie nagłego podmuchu wiatru.
12 grudnia 2019
mgr Karolina Dziadura (IOA)
Projekt „Eclipse de Sol Chile 2019” był ekspedycją do Chile w celu obserwacji całkowitego zaćmienia Słońca. W wyprawie uczestniczyli studenci i doktoranci z Uniwersytetu im. Adama Mickiewicza w Poznaniu, Uniwersytetu Artystycznego w Poznaniu oraz Uniwersytetu Mikołaja Kopernika w Toruniu. Całkowite zaćmienie Słońca obserwować można było w Chile 2 lipca 2019 roku. Na miejsce rejestracji wybraliśmy górę na wybrzeżu Pacyfiku, w regionie La Higuera (29.4544° S, 71.2472° W, 795 m n.p.m.). W tym miejscu całkowite zaćmienie Słońca trwało 2 minuty 35.8 sekundy. Pierwszy kontakt Słońca z Księżycem nastąpił o godzinie 19:22:53.6 UT. Początek, maksimum i koniec fazy całkowitego zaćmienia przypadł odpowiednio na 20:38:24.0 UT, 20:39:42.1 UT i 20:40:59.8 UT. Słońce znajdowało się wtedy na wysokości 13.6° i azymucie 306.8°. Do rejestracji użyliśmy: aparatu Canon 6D z teleobiektywem 100-400 mm (fotografie), aparatu Canon 650D z obiektywem 150 mm (film), aparatu Nikon D90 z obiektywem 200 mm (fotografie), aparatu Canon 700D z obiektywem 800 mm (fotografie). Ponadto wykonaliśmy rejestrację trajektorii Słońca na nieboskłonie za pomocą urządzenia meteorologicznego zwanego heliografem.
5 grudnia 2019
mgr Monika Kamińska (IOA)
Obserwacje optyczne obiektów na niskich orbitach okołoziemskich
28 listopada 2019
prof. David Vokrouhlický (Astronomical Institute of Charles University, Prague)
Traditionally, long-period comets (LPC) are defined by their huge orbital periods: 200 yr at minimum, but many have effective orbital periods as long as millions of years. At the first sight, they are mysterious visitors to the inner Solar system on incomparably elongated orbits from its extreme outskirts. Yet, their population may be well understood using advances in our knowledge of the Solar system early evolution and a flood of new and accurate orbital data. I shall describe an evolutionary model for the LPCs that reasonably well matches their orbital architecture. Admittedly, it is less successful in describing their observed flux to the inner Solar system, though I shall discuss plausible reasons for this mismatch. The model allows to make predictions which could be tested by LSST observations within the next decade.
21 listopada 2019
dr Arkadiusz Hypki (IOA)
Project gaia@home (former GAVIP-GridComputing) is an ESA project run by Poznan Astronomical Observatory staff which will add additional features to the Gaia archive by incorporating CPU power of volunteers’ computers of the BOINC grid (best known of its SETI@Home project).
gaia@home eventually will allow to define a series of jobs which will be able to read entire Gaia archive and compute some CPU intensive jobs on the BOINC platform (best known from SET@home project). The users, in order to use the GAVIP-GC software will provide source code to deal with their scientific problem. Everything else (e.g. reading data from Gaia, communicating with BOINC, downloading the results) will be done by gaia@home software.
During the seminar I will present the current status of the project.
14 listopada 2019
dr hab. Anna Bartkiewicz (UMK Toruń)
High angular resolution studies of the 6.7 GHz methanol maser emission provide one of the best existing tools for deriving 3D kinematics around high-mass proto- or young stars. Regions that are hidden in the dense environments and are not easily reachable at other wavelength ranges. Particularly, multi-epoch, sensitive observations using the very long baseline interferometry networks are successfully used to investigate proper motions of single maser clouds in high-mass star forming regions.
I will present recent studies of sources that showed ring-like structures at the 6.7 GHz line and were discovered in the Torun survey with the 32-m radio telescope. Using the European VLBI Network over 10 years and obtaining images of emission with miliarcsecond angular resolution, we can follow detailed kinematics (tangential velocities of order a few km/s) of masing clouds in the vicinity (ca. 1000 au) from central stars. Unexpectedly, masers are expanding from the centres of the ring, indicating a physical relation to an outflow or an expanding bubble rather than a disc.
7 listopada 2019
dr Krzysztof Kamiński (IOA)
We wrześniu/październiku 2019 w Chalinie zainstalowano cztery kopuły oraz teleskopy i montaże nowego systemu do obserwacji satelitarnych PST3. Omówione zostaną podstawowe etapy budowy systemu. Przedstawiona zostanie foto relacja z budowy. Zaprezentowane będą podstawowe parametry techniczne pięciu teleskopów oraz pozostałego sprzętu. Omówione zostaną możliwości systemu, dalsze plany budowy oraz testowe obrazy z niektórych teleskopów.
24 października 2019
dr Magdalena Otulakowska-Hypka (IOA)
Interferometria optyczna jest metodą obserwacji, która łączy światło zbierane przez kilka teleskopów obserwujących jednocześnie ten sam obiekt astronomiczny. Pozwala ona wyznaczyć rozmiary, a nawet dokładne kształty obiektów astronomicznych. Używamy interferometrii optycznej do zbadania jak największej liczby gwiazd symbiotycznych. Nasze obserwacje i analiza pozwolą nie tylko wyznaczyć wielkości gwiazd, ale dzięki temu, że dotrzemy do najbardziej wewnętrznych części tych układów podwójnych, będziemy mogli bezpośrednio zaobserwować rozciąganie się powierzchni czerwonego olbrzyma wskutek działania sił pływowych. Przedstawię pierwsze wyniki tego projektu.
17 października 2019
dr John Williamson (University of Glasgow)
A new theory of light and matter incorporates a complex scalar field, responsible for the mutual confinement of light and rest mass in “elementary” particles. This field parallels many of the observed properties of dark matter and dark energy. These include the gravitational effects, the property of the observed increase in the rate of “expansion” of the universe, the transparency of the substance to light and the non-observation of dark matter to date. This invisibility does not mean that the substance is immune to experiment. Experimentally observable effects of this field in the nearby solar system, the local galactic cluster and the wider universe will be discussed. As well as the usual properties associated with dark matter/energy such as gravitational lensing, the observed expansion of the universe and galactic rotation, the talk will discuss, among other things, solar coronal heating, high energy particle generation (x and gamma rays and high-energy charged particles), and matter-antimatter asymmetry in the physical universe.
John Williamson worked at CERN for 7 years, in nano engineering in Philips for 5 years, and as an associate professor in the College of Science and Engineering in Glasgow University for 27 years. He is currently the director of Quicycle an international group devoted to the advancement of science. He has published widely in the fields of experimental physics, nano-engineering, and in theoretical physics. He has (co-) authored over a hundred papers. He has over twelve thousand citations in peer-reviewed papers and an h-index of 45.
10 października 2019
mgr Rita Wysoczańska (IOA)
Odkąd w 1950 roku Oort opublikował swoją pracę na temat pochodzenia komet trwają nieprzerwane prace nad znalezieniem gwiazd, które mogły istotnie wpłynąć na ich ruch. Celem tej prezentacji jest przedyskutowanie dwóch przypadków, w których wykorzystano dane pochodzące z obserwacji, i w których wykryto oddziaływanie gwiazd na komety. Wyniki pokazują jak wyglądałaby dynamiczna ewolucja komet gdyby ich ruch był rozpatrywany tylko w potencjale grawitacyjnym Galaktyki. W naszych badaniach uwzględniliśmy niepewności danych gwiazdowych i kometarnych. Analiza wykazała, że przypadki wpływu gwiazd na dynamikę komet są rzadkie, a niepewności tych efektów są trudne do oszacowania.
W roku akademickim 2018/2019 wystąpili:
6 czerwca 2019
mgr Emil Wilawer (IOA)
At the beginning of XXI century astronomy entered the Big Data era, in which robotic telescopes produce petabytes of data. Most of them consist of CCD images which require automatic measurements by the specialized photometric pipelines. In our Institute we still use a traditional method of aperture photometry which requires frequent manual intervention. While beeing well tested, this approach starts showing its weekness when faced with the increasing inflow of observing data. It also lacks photometric callibration which recently became a routine procedure in differential photometry thanks to the sky surveys (SDSS, PanSTARSS) which released their high accuracy photometric measurements of millions of stars. In the talk I will present the use of the photometric pipeline of Michael Mommert for the automatic photometry of asteroids and briefly describe main stages of the computations The application of this procedure for derivation of asteroid phase curves will also be shown.
30 maja 2019
mgr Piotr Guzik (OA UJ)
Discovered last year, the first recognized interstellar visitor in Solar System, 1I/2017 U1 (Oumuamua) is the long-sought link between our own Solar System and systems around other stars, heralding an onset of a new field in astronomy. Our group has played an important role in the effort of characterizing this unique body. We were awarded 12 hr of DDT on the Gemini North 8.1-m telescope. As a result, we obtained the highest quality photometric and spectroscopic data, which have revealed some remarkable and unexpected properties. I will review the current state of knowledge on Oumuamua, discuss the impact of this body on science and society, and speculate on possible future avenues.
In the second part of my talk, I will present our first dedicated search for dust trails of asteroids, that forms along the asteroids orbit as a result of their disruptions. The trail can be observed for many years, as showed by the studies of two recently disrupted asteroids, P/2010 A2 and P/2012 F5. We argue that a dedicated survey with a large telescope can possibly detect much fainter (thus older) trails – precious remnants from historical disruptions – thereby providing basis for detailed research into the causes of the disruption. A pilot survey was conducted by our team at SALT. We have successfully detected the known ultra-faint trail of the disrupted asteroid P/2012 F5 – proving the concept in terms of technical feasibility. I will present the main science goals of the survey, discuss the results from the pilot phase, and draw conclusions for the full phase which has been recently initiated.
23 maja 2019
mgr Jacek Haponiak (IOA)
Model “Bąk Colmobo” opisuje dynamikę obrotową bryły sztywnej obiegającej punkt materialny pod wpływem siły grawitacji. Model ten może mieć zastosowanie do badania ruchu obrotowego Księżyca, planet w Układzie Słonecznym, planet pozasłonecznych, księżyców, planetoid i śmieci kosmicznych. W prezentacji zostanie przedstawiony model “Bąk Colombo”, jego zastosowania, a także jego analityczne rozwiązanie.
16 maja 2019
prof. Tomasz Kwiatkowski (IOA)
Working under a contract to ESA we are preparing a web-based Service for Archival NEO Orbital and Rotational Data Analysis (SANORDA). It includes a NEO Period Determination Tool (NPDT) which takes asteroid lightcurves from a database and uses them to derive their rotation periods. The algorithm is based on a well known Fourier series analysis and implemented as a python program called PerFit. In the talk I will present a typical use cases of the NPDT service, which is currently in a beta stage. Using PerFit I will also show how the uncertainties in the asteroid lightcurves influence the accuracy with which their synodic periods can be derived.
25 kwietnia 2019
mgr Volodymyr Troiansky (IOA)
Basaltic V-type asteroids and their fragments are collisional remnants of planetesimals that existed 4 billion years ago. Their distribution, physical and dynamical properties provide important constrains on processes such as planetary differentiation, planet formation and evolution of planetary systems.
Asteroids with the prograde sense of rotation, located in the inner Main Belt, that have semi-major axes of their orbits smaller than that of Vesta, are less likely to have migrated from Vesta due to thermal forces dragging them outwards (the Yarkovsky effect).
Assuming that the inner Main Belt is populated only by the Vesta like objects, around 81% of asteroids in the so-called scattered resonances region are expected to have retrograde sense of rotation. Similarly 40% of objects in the low inclination region, should have retrograde rotation. Substantial surplus of asteroids that have prograde rotation could indicate that also other planetesimals (different from Vesta) contributed to this population. Those predictions are verifiable via photometric studies in which asteroid lightcurves are used to derive senses of rotation.
4 kwietnia 2019
prof. Piotr Dybczyński (IOA)
Na temat pierwszego makroskopowego gościa z przestrzeni międzygwiazdowej ukazało się dotąd prawie 60 publikacji. Obserwowało go kilkanaście najpotężniejszych teleskopów naziemnych i orbitalnych. Niestety tak krótka wizyta skutkuje wielkimi lukami w wiedzy na temat tego obiektu a to co wiemy przynosi nam więcej zagadek niż odpowiedzi. Posunięto się nawet w poważnej literaturze astronomicznej do sugerowania sztucznej natury tego obiektu jako tworu obcej cywilizacji. Większość badaczy jednak odrzuca takie spekulacje. Obiekt ten świetnie pasuje do swej nazwy — jest równie dziwny i tajemniczy.
28 marca 2019
mgr Patrycja Bagińska (IOA)
Rozbłyski nowych rentgenowskich (Soft X-ray Transients; X-ray Novae) są powodowane przez niestabilność jonizacyjną zachodzącą w zewnętrznych rejonach dysku akrecyjnego. Rozbłyski pojawiające się w wyniku tej niestabilności przyjmują charakterystyczny kształt związany z szybkim wzrostem jasności i jej eksponencjalnym zanikiem (profil FRED – fast rise exponential decay). Moja praca obejmowała badanie układów rentgenowskich, których obiektami centralnymi są czarne dziury. W ramach moich badań policzyłam modele rozbłysków przy pomocy kodu uwzględniającego ewolucję niestabilności w dysku akrecyjnym, strukturę wertykalną dysku oraz parametr lepkości. Utworzona przeze mnie baza modeli obejmowała różne kombinacje parametrów takich jak masa czarnej dziury, tempo akrecji czy krok czasowy i została utworzona dla ustalonego składu chemicznego dysku akrecyjnego (skład typu słonecznego). Dodatkowo wykonałam symulacje krzywych stabilności i modeli dla różnych składów chemicznych dysków akrecyjnych, żeby ustalić, z jakiego typu dyskami mamy do czynienia w obserwowanych obiektach. Zmiana składu chemicznego dysku (zwiększenie zawartości metali) powoduje powstawanie chaotycznych rozbłysków o niesymetrycznej strukturze, które pasują do danych obserwacyjnych. W wyniku dopasowania modeli do obserwacji uzyskałam potwierdzenie, że mechanizmem odpowiedzialnym za powstawanie rozbłysków w badanych systemach jest niestabilność jonizacyjna. W wyniku modelowania możliwe było również oszacowanie masy obiektu centralnego (czarnej dziury) i tempa akrecji na zewnętrznej części dysku.
21 marca 2019
mgr Mikołaj Krużyński (IOA)
Budowanie katalogu satelitarnego związane jest z systematycznymi obserwacjami ponad 20 tysięcy obiektów. Wymagana jest duża precyzja obserwacji pozycji satelity oraz precyzyjny pomiar czasu. Trzeba również uwzględnić szereg sił perturbujących, które mają wpływ na orbitę satelity. Do uwzględnienia tych wszystkich efektów niezbędne jest odpowiedni proces przeprowadzenia obserwacji i ich redukcji oraz specjalistyczne oprogramowanie. Chociaż obserwacje obiektów satelitarnych są wykonywane od ponad 60 lat, to wykorzystanie teleskopów w przypadku obiektów poruszających się poniżej 2000 km nad powierzchnią Ziemi jest nowością. Dopiero rozwój technologiczny, który nastąpił przez ostatnią dekadę, pozwolił na wykonywanie odpowiedniej jakości obserwacji astrometrycznych satelitów na orbitach typu LEO (Low Earth Orbit). I chociaż wciąż najdokładniejsze pomiary satelitarne wykonuje się przy użyciu dalmierzy laserowych to zakres ich użycia oraz wysoki koszt stanowią pewne ograniczenie w ich stosowaniu. Dlatego wykorzystanie pomiarów laserowych i astrometrycznych dla satelitów na orbitach LEO może prowadzić do uzyskania jeszcze lepszych wyników pomiarowych, a co za tym idzie jeszcze lepszego wyznaczenia orbity obserwowanego satelity. W czasie wystąpienia zostaną zaprezentowane wstępne wyniki pokazujące możliwość łączenia danych obserwacyjnych wykonanych przy użyciu różnych technik pomiarowych.
14 marca 2019
dr hab. Michał Michałowski (IOA)
I will present the results of observations (including those with RBT/PST2) of a gamma-ray burst (GRB) 171205A and the associated supernova (SN) 2017iuk, which led to the discovery of a hot gas cocoon. This was possible because observations started very early and the jet emission was weak. This gives support to the theoretical models of GRB/SN explosions, which predicted the existence of such a cocoon. This discovery opens the possibility to study internal processes during explosions of very massive stars, and hence will shed light on the understanding of the production of heavy elements. In case you miss this seminar, I will also give it at the Faculty of Physics on 3rd of April:
http://zon8.physd.amu.edu.pl/~miran/seminars.html
24 stycznia 2019
prof. Mirosław Giersz (CAMK PAN)
I will very briefly describe the basic ideas behind the Monte Carlo MOCCA code and discuss the set-up of the MOCCA Survey Database project – a database containing thousands of Monte Carlo (MOCCA) simulations of real globular clusters. Afterwards, I will list and shortly describe projects connected with the analysis of the Database from the point of view of compact objects. Projects which deal, among others, with: BH and NS populations in star clusters and their interactions, BH Subsystems and IMBHs and their observational signatures, and many more. Finally, I will discuss recent developments of the MOCCA code and planed simulations for the MOCCA Survey Database II.
17 stycznia 2019
mgr Krystian Iłkiewicz (CAMK PAN)
Cataclysmic variables (CVs) are interacting binary stars that consists of a degenerate white dwarf accreting mass from a normal star donor. Our understanding of evolution of such systems have been challenged by properties of their known population, such as white dwarf mass distribution, orbital period distribution and their space density. With the recent developments of population synthesis codes we are able to reproduce the CV population characteristics. However, there are still unsolved problems posed by the population of classical novae among the CVs, such as for example why there is only one system known to have both dwarf nova and classical nova outbursts. In my talk I will discuss the recent developments of population synthesis codes as well as my work on understanding of classical novae population using population synthesis.
10 stycznia 2019 (dwa krótsze referaty)
mgr Aleksandra Leśniewska (IOA)
Binary stars are very important topic of astrophysical research. Using the data from photometric and spectroscopic observations, we are able to determine much more physical parameters of the system’s components than in the study of a single star. We obtain information not only about effective temperatures, metallicity, rotation velocity, but what is the most important, masses and radii of two components. Compact binaries become crucial when considering the evolution of stars and their influence on the later generations of astronomical objects. The system composed of a white dwarf and a red giant, is called symbiotic star. Researches on these types of objects contribute to a more accurate understanding of the geometry of binary stars and mechanisms in these systems. Our work is dedicated to modeling the physical parameters of the SY Muscae, symbiotic star in the southern sky. Based on photometric and spectroscopic observational data, in the infrared and visible range, using the PHOEBE program we created a model of light curves and radial velocity. This model clearly describes the shape and dimensions of the components of SY Muscae. The result of the analysis is a model of light curves, radial velocity, and a set of SY Muscae physical parameters. Based on the comparison of the results obtained by us with the results in the literature, it turns out that SY Muscae is a typical symbiotic star.
Dust production is a very important issue in galaxy evolution. Unfortunately, we are still unable to determine its formation mechanism. I will present the investigation of dust production in nine galaxies at the redshift at z > 6, for which dust emission has been detected. In recent years, more accurate measurements were made using the most powerful instruments, eg ALMA, which contributed to better estimates of luminosities and sizes, and thus to determine the masses of gas, dust and stars in the studied galaxies. We conclude that asymptotic giant branch (AGB) stars did not contribute to the dust formation significantly in these Early Universe galaxies, and that supernovae are unlikely to produce the bulk of the dust mass. I will discuss how the advent of future large telescopes will contribute to this topic.
21 grudnia 2018 (Dodatkowe seminarium o 13:30 dla chętnych)
dr Anna Kapińska (National Radio Astronomy Observatory, USA)
The new continuum radio surveys delivered in recent years are an outstanding resource in addressing long-standing questions in modern astrophysics. In this talk I will focus on the lowest radio frequencies (<230MHz) currently accessible with the ground based new-generation radio facilities. Specifically, I will present our recent results on radio spectral energy distributions and star formation of Sculptor Group galaxies and Magellanic Clouds, which we observed with the Murchison Widefield Array (MWA) — a low frequency SKA precursor from an Australian outback. Although of low angular resolution, especially as compared to ALMA, these sensitive low frequency observations are very complementary to GHz observations, and necessary for a complete picture of physical processes occurring in galaxies.
20 grudnia 2018
dr Agata Makieła (University of Kent, UK)
In the summer 2017 I was involved in the NASA Frontier Development Lab, an intense 8-week study concentrated on tackling topics important to NASA using machine learning tools. During the programme interdisciplinary teams of early career researchers were looking at issues related to planetary defence, space weather, and space resources. The team I was a part of investigated shape modelling of near-Earth asteroidsfrom radar data. These asteroids are the Earth’s closest neighbours in space, most accessible by space flight and with a potential for causing a threat to the planet. Even though they are constantly monitored, detailed characteristics, like shapes and sizes, are available for only a selected few. Physical models are required to successfully plan spacecraft missions and set up impact mitigation strategies. Additional incentive is in learning know how our space environment works and evolves. Reconstructing asteroid shapes and spins from radar data is, like many inverse problems, a computationally intensive task. Shape modelling also requires extensive human oversight to ensure that computational methods find physically feasible results. In this talk I will discuss the results of our work at NASA Frontier Development Lab 2017, exploring the application of machine learning tools to the shape modelling task.
13 grudnia 2018
dr Krzysztof Hełminiak (CAMK PAN)
In years 2015-2017 we have conducted a programme of high-resolution spectroscopic observations of a sample of detached eclipsing binaries (DEBs) observed by the Kepler satellite in its original mission field. With the 1.88-m telescope of the Okayama Astrophysical Observatory and its HIDES spectrograph, we have collected 290 spectra of 23 systems, in order to analyse them thoroughly and as comprehensively as possible. The sample contains variety of different objects (giants, low-mass stars, multiples, pulsators, planet hosts), many of which were studied for the first time, and with parameters derived very precisely. In my semi-formal talk I will present a subjective selection of 10 systems from our sample that I find the most interesting, intriguing and important for the stellar astrophysics. Kittens will be included.
10 grudnia 2018 (Dodatkowe seminarium o 16:00 dla chętnych)
dr José Ricardo Rizzo Caminos (Centro de Astrobiologia, Madrid)
Opportunities using radio astronomy facilities in Madrid
6 grudnia 2018
dr Arkadiusz Hypki (IOA)
GAVIP-GridComputing (shortly GAVIP-GC) is an ESA project run by Poznan Astronomical Observatory staff which will add additional features to the Gaia archive by incorporating CPU power of volunteers’ computers of the BOINC grid (best known of its SETI@Home project). GAVIP-GC eventually will allow to define a series of jobs which will be able to read entire Gaia archive and compute some CPU intensive jobs on the BOINC platform. The users, in order to use the GAVIP-GC software will have to provide only source code to deal with their scientific problem. Everything else (e.g. reading data from Gaia, communicating with BOINC) will be done by GAVIP-GC software. During the seminar I will present the current status of the project and our plans for the next milestones.
29 listopada 2018
prof. David Vokrouhlický (Astronomical Institute of Charles University, Prague)
Asteroid families are clusters of small bodies that move about the Sun on fairly similar orbits. They are outcome of a collisional disruption of a common parent asteroid. Therefore, analysis of members in families can bring us interesting information about the fragmentation process at high-energies and, otherwise inaccessible, interior properties of asteroids. The most valuable in this type of studies are young families, in which the evolutionary processes had not enough time to confuse the results. I will review the past two decades of a race to find ever younger families in the main belt, demonstrating also what kind of unexpected results it brought along.
22 listopada 2018
prof. Edwin Wnuk (IOA)
Od 2019 roku Polska jako kraj członkowski Europejskiego Konsorcjum EU SSA (Space Situational Awareness) rozpocznie świadczenie usług SST (Space Surveillance and Tracking). W związku z tym, od pewnego czasu trwają intensywne prace, których celem jest zbudowanie Polskiego Systemu PL SST, który w przyszłości zostanie rozszerzony do PL SSA.
SSA składa się z trzech następujących segmentów:
Space Weather (SWE) – monitorowanie Słońca, wiatru słonecznego oraz ziemskiej magnetosfery, jonosfery i termosfery,
Near-Earth Objects (NEO) – detekcja i monitorowanie ruchu orbitalnego obiektów naturalnych, takich jak planetoidy i komety, które mogą zbliżać lub zderzyć się z Ziemią,
Space Surveillance and Tracking (SST) – detekcja, śledzenie i monitorowanie ruchu orbitalnego aktywnych i nieaktywnych satelitów oraz śmieci kosmicznych.
Polski System SST będzie składał się z Narodowego Centrum Operacyjnego (NOC), sieci kilkunastu teleskopów optycznych oraz stacji laserowej w Borowcu. Będzie ściśle powiązany z systemami EU SST i ESA SST oraz z europejskim centrum danych satelitarnych SATCEN. System PL SST, w pierwszym okresie działania, będzie świadczył dwie usługi dla EU SST: RE – Re-Entry oraz FR – Fragmentation, a później także CA – Collision Avoidance. Na potrzeby tych serwisów, a także na potrzeby krajowych odbiorców usług SST, będą wykonywane obserwacje wybranych obiektów satelitarnych, wyznaczane orbity tych obiektów oraz będzie tworzony i aktualizowany Katalog Satelitarny.
W referacie zostaną przedstawione aktualne informacje związane z tworzeniem systemu PL SST, w szczególności struktura organizacyjna i potrzeby softwarowe Centrum Operacyjnego. Opisane zostaną także krótko podstawowe serwisy SST, a także problemy związane z tworzeniem Katalogu Satelitarnego.
15 listopada 2018
prof. Jerzy Krzesiński (OA UJ)
We are showing that some of the exoplanetary signatures found in the light curves of a couple of sdBV star systems (KIC 5807616 and KIC 10001893) might be of different source than exoplanet light reflection or radiation effects. We point out that at least one signature can be explained by a combination of pulsating frequencies of the host star and others might be just artifacts. Using simulated light curves we also analyzed frequency changes of the signal around 0.256 c/d (~3.9 day) visible in the Fourier transform of the KIC 10449976 sdO star light curve. Our simulations show that it is difficult to reproduce the observed signal frequency variations by the weather changes in the exoplanet atmosphere.
8 listopada 2018
dr Justyna Gołębiewska (IOA)
From the launch of the first artificial satellite: Sputnik in 1957, more than 5000 launches have placed 8000 satellites into orbit, of which about 4800 remain in space. In addition to operational satellites in orbit there are over 12000 space debris. To to ensure safety in space European Space Agency (ESA) as well as European Commission carries out the Space Situational Awareness (SSA) Programme, consisting of three segments. One of these segments is the Space Surveillance and Tracking (SST) system that comprises detecting,cataloguing and predicting the orbits of objects orbiting the Earth, and related applications. We are showing our results in two of main segment of SST: Re-entry Predictions for Risk Objects and Collision Warning.
25 października 2018
prof. Tadeusz Jopek (IOA)
Wyszukiwano grupy pomiędzy planetkami typu NEA. Zastosowano dwie D-funkcje oraz rygorystyczny algorytm analizy skupień. Zidentyfikowano kilka nowych grup – obiektów poruszających się po orbitach z niewielkimi wartościami MOID względem orbity Ziemi.
18 października 2018
dr Krzysztof Kamiński (IOA)
In recent years European Space Agency (ESA) as well as newly established European Space Surveillance and Tracking Consortium (EU SST) — both of witch Poland is a member state — have increased the effort towards a new satellite tracking system for Europe, that would be independent from external sources of satellite orbital data. Such a system is typically composed of several radar sensors for tracking Low Earth Orbit (LEO) satellites and several optical sensors for higher orbit targets. However recent developments in optical telescopes enabled an efficient tracking of LEO satellites with an equipment 2 to 3 orders of magnitude cheaper than a typical satellite radar. Of course optical satellite sensing suffers from a daytime and bad weather limitations to a much greater extent than a satellite radar. Therefore it is reasonable to simulate an optical satellite tracking network, using a global cloud-fraction statistics, in order to estimate possible outcome from such an entertainment. In this seminar I present preliminary results of simulations showing weather it is possible to build an efficient global optical satellite tracking network, what locations should be selected on Earth, and how many sites should be used in order to have a very high probability of observing each target every day.
11 października 2018
dr hab. Agnieszka Pollo (OA UJ)
I will present recent results from the VIMOS Public Extragalactic Redshift Survey (VIPERS). VIPERS – with its \sim 90,000 spectroscopically measured galaxies, a large volume (5 x 10^7 h^(-3) Mpc^3), and an effective spectroscopic sampling > 40% – can be considered the state-of-the-art counterpart of “local” (z<0.2) cosmological surveys but targetting the epoch at z \sim 1. I will summarize our newest results on the properties of galaxies and large scale structure and their common evolution since z \sim 1. How galaxies changed during the last 8 bln years? What are the properties of the 3D cosmic structure emerging from VIPERS measurements and what they can they tell us about cosmological parameters? And, most interestingly – what remains unknown and why do we need even larger surveys in the future?
4 października 2018
Sprawy organizacyjne
W roku akademickim 2017/2018 wystąpili:
21 czerwca 2018
mgr Grzegorz Dudziński (IOA)
The volume of an asteroid shape model, when combined with the size and mass estimates, is essential in bulk density determination – one of the most important physical parameters that allow us to peek inside asteroids and make conclusions about their inner structure. The shape model uncertainty propagates to volume, and analogously to any
other property determined from the model, affecting every conclusion drawn for a population of small bodies under scrutiny. There definitely exists a compelling need for a procedure of quality and uncertainty assessment of asteroid models. I would like to present modelling-technique-independent uncertainty assessment method based on gen-
erating clones of investigated model. By far, the most abun-dant data type for the most numerous target sample is disc-integrated relative photometry in visual bands and the majority of published asteroid models are based solely on it. For that reason the presented method deals with photometric lightcurves and absolute sparse data.
14 czerwca 2018
dr Milena Ratajczak (IA UWr)
Several aspects of stellar evolution can be tested with B-type stars in eclipsing binary systems. Finding tighter constraints on the value of the convective core overshooting parameter is one of the most valuable among them. Precise photometry and high-resolution spectroscopy with high SNR are required to achieve that goal, but since many of the targets are bright enough, the challenge is fair. The approach to examine the aforementioned aspect of stellar evolution using observations of B-type stars obtained with a wide range of spectrographs, as well as BRITE-Constellation satellites, will be presented.
7 czerwca 2018
dr Magdalena Otulakowska-Hypka (IOA)
The disk instability model attributes the outbursts of dwarf novae to a thermal-viscous instability of their accretion disk, an instability to which nova-like stars are not subject. We aim to test the fundamental prediction of the disk instability model: the separation of cataclysmic variables (CVs) into nova-likes and dwarf novae depending on orbital period and mass transfer rate from the companion. We analyse the lightcurves from a sample of ~130 CVs with a parallax distance in the Gaia DR2 catalogue to derive their average mass transfer rate. The method for converting optical magnitude to mass accretion rate is validated against theoretical lightcurves of dwarf novae. Dwarf novae (resp. nova-likes) are consistently placed in the unstable (resp. stable) region of the orbital period – mass transfer rate plane predicted by the disk instability model. None of the analyzed systems present a challenge to the model. These results are robust against the possible sources of error and bias that we investigated. The disk instability model remains the solid base on which to construct the understanding of accretion processes in cataclysmic variables.
24 maja 2018
mgr Przemysław Mróz (OA UW)
Theories of planet formation predict the existence of a population of unbound (free-floating) planets. Gravitational microlensing provides a unique tool for studying these objects. The first results of Sumi et al. (2011) claimed that Jupiter-mass free-floating planets are as common as main-sequence stars. However, these results appear to disagree with censuses of substellar objects in young clusters and star-forming regions and with predictions of planet formation theories. I will present new results of the analysis of a ten times larger sample of microlensing events discovered by the OGLE-IV survey during the years 2010-2015. They shed new light on the population of free-floating planets.
17 maja 2018
mgr Ewa Kosturkiewicz (IOA)
Wstępne wyniki spektroskopowej kampanii obserwacyjnej gwiazdy delta Ceti w latach 2014 – 2017
10 maja 2018
mgr Krzysztof Langner (IOA)
Transformacja Kustaanheimo-Stiefela (KS) pozwala zregularyzować zagadnienie dwóch ciał i sprowadzić je do liniowej postaci oscylatora harmonicznego. Regularyzacja polega na zmianie zmiennej niezależne (czasu) i pozwala między innymi zwiększyć dokładność obliczeń numerycznych, zwłaszcza w przypadku orbit o dużym mimośrodzie. Transformacja Lissajous pozwala wprowadzić zmienne kąt działanie dla oscylatora harmonicznego. W trakcie prezentacji przedstawione zostanie połączenie obu transformacji, używając formalizmu kanonicznego oraz ich rozszerzenie pozwalające stosować ten formalizm w przypadku orbit z zaburzeniem jawnie zależnym od czasu.
26 kwietnia 2018
dr Agnieszka Słowikowska (CA UMK)
In my talk, I will describe the basic concept of polarimetry as well as the most common use of it as a tool in astronomy. I will present a few polarimeters that are in use at the moment. Additionally, I will discuss our recent polarimetry study of white dwarfs and neutron stars.
19 kwietnia 2018
prof. Andrzej Niedzielski (CA UMK)
Stars beyond the MS are frequently avoided in planet searches because they are known to exhibit various types of variability: RV variations of unknown origin were pointed out to be common in red giants (RGs) by Walker et al. (1989), and multiple pulsation modes are often present. In addition, the rotation of starspots across the stellar disk can affect the spectral line profiles of these stars (Vogt et al. 1987; Walker et al. 1992; Saar & Donahue 1997). However, soon after the first discovery (ι Dra b Frink et al. 2002), searches for planets around stars beyond the MS have become recognised as important in building a complete picture of planet formation and evolution for several reasons. First, they allow extending the reach of the most versatile RV technique, which is not applicable on the MS because of the high effective temperature of the stars and their fast rotation rates, to objects with masses significantly higher than solar (e.g., o UMa, a 3 M⊙ giant with a planet – Sato et al. 2012). Second, the planetary systems around evolved stars are much older than those around MS stars, and therefore they are suitable for long-term dynamical stability considerations. Planetary systems around giants are also subject to changes induced by stellar evolution, and therefore are suitable for studies of star – planet interactions, and last but not least, evolved planetary systems carry information on the initial population of planetary systems to be found around white dwarfs. It is no surprise then that several projects devoted to searches for RV planets that orbit RGs were launched. One of the largest of them is the PennState – Toruń Centre for Astronomy Planet Search (PTPS, Niedzielski et al. 2007; Niedzielski & Wolszczan 2008a,b).
In my talk I will present the sample of PTPS, current status of our planet search and the most recent discoveries. I will also discuss some properties of the exoplanets around evolved stars from the PTPS perspective.
12 kwietnia 2018
prof. Agata Różańska (CAMK)
X-ray astronomy requires satellites to make progress in searching the distribution of hot matter in the Universe. Approximately 15 years period of time is needed for full construction of the flight instrument from the mission concept up to the launch. A new generation X-ray telescope ATHENA (the Advanced Telescope for High Energy Astrophysics) was approved by European Space Agency as a large mission with a launch foreseen in 2028. I will talk about how ATHENA will help us to study Hot and Energetic Universe, and I will present Polish involvement to the mission development.
5 kwietnia 2018
dr Michał Drahus (OA UJ)
Disruptions of asteroids are often viewed as ancient events leading to the
formation of asteroid families and pairs, binary and multiple systems, and
discrete dust bands within the Zodiacal cloud. But thanks to the
remarkable progress in solar system science over the last decade, we can
now directly observe asteroidal disruptions occurring before our eyes.
Various lines of evidence suggest that the disruption can be a consequence
of a rapid rotation resulting from a long-term spin-up, or a result of a
hypervelocity collision with another minor object. Up until recently the
two mechanisms were difficult to distinguish because of the unknown
rotation rates of the disrupting small asteroids, but this has changed
after our team investigated the recently disrupted asteroid P/2012 F5.
Using the Keck II telescope atop Mauna Kea we discovered several fragments
of the object and obtained the highly anticipated measurement of the
rotation rate, which turns out to be the fastest known among active
asteroids and is fast enough to support the rotational disruption
scenario. Further observations with the Hubble Space Telescope have
revealed that the system is in fact the first ultra-young asteroid family
identified to date, and given its likely formation via rotational
disruption, it can also be the first known asteroid family of
non-collisional origin.
22 marca 2018
prof. Agnieszka Kryszczyńska (IOA)
The NEO-DECS web service an open access central service of structured
metadata on NEOs, as well as a platform for collaboration among NEO
researchers, using elements well known in social networking like user
profiles, forum facility, private messaging, etc. Such service shall make
it easy to locate necessary databases and services on NEOs, learn about
forthcoming conferences and workshops, and allow for advertising new
observing programs, telescopes availability, numerical tools, etc.
During the talk I will demonstrate NEO-DECS based on several use cases.
15 marca 2018
Seminarium odwołane
8 marca 2018
prof. Edwin Wnuk (IOA)
Polska Agencja Kosmiczna przygotowała projekt Krajowego Programu Kosmicznego
(KPK) i przedstawiła jego pierwszą wersję w grudniu 2017 r. Po
konsultacjach z różnymi zaineresowanymi środowiskami KPK ma być zatwierdzony
do realizacji w pierwszym kwartale 2018 r., po czym maja być ogłoszone
pierwsze konkursy merytoryczne obejmujące szeroki zakres zagadnień z zakresu
badań kosmicznych, w tym również z zakresu astronomii.
W trakcie wystąpienia seminaryjnego zostaną przedstawione podstawowe
informacje o KPK, zostaną omówione trzy projekty priorytetowe KPK oraz
wymienione zostaną obszary zagadnień, w których zostaną rozpisane konkursy
grantowe. Podane zostaną też podstawowe informacje dotyczące zasad
wnioskowania o projekty KPK oraz informacje o planowanym budżecie KPK.
Przedstawione na seminarium informacje będą dotyczyły głownie obszarów
naukowego i edukacyjnego w KPK.
1 marca 2018
dr Magdalena Polińska (IOA)
We would like to present results for the two objects, GT UMa B which is a part of multiple system and for the eclipsing binary star BD-00 2862. The spectra for the first object were obtained with the spectrograph ESPERO mounted on the 2-m telescope in Rozhen and for the second one with PST1 (Poznań Spectroscopic Telescope 1) located in Borowiec. For those stars we estimated atmospheric parameters, such as: the effective temperature, surface gravity, metallicity and the projected rotational velocity. The observed spectra were compared with the set of synthetic spectra calculated with the iSpec code.
22 lutego 2018
dr Arkadiusz Hypki (IOA)
The amount of data in science which is delivered nowadays increases like never before. It applies for all fields of research. However, physics and astrophysics appear to push the requirements for data storage and analysis to the boundaries. With already existing missions like Gaia and for future projects like LSST the need for reliable and scalable data storage and management is even higher. The amount of data for many projects is too big for simply processing with bash or python scripts. Tools which would allow easy data analysis are crucial in research these days.
BEANS software is a web based, easy to install and maintain, new tool for interactively distributed data analysis. It provides a clear interface for querying, filtering, aggregating, and plotting data from an arbitrary number of datasets and tables.
During the seminar I will present features of the BEANS software and show how it can help scientists to analyze huge datasets.
25 stycznia 2018
dr An-Li Tsai (IOA)
Galactic molecular outflows affect star formation activities in galaxies. This process is important for galaxies evolution. I will talk about case studies on two nearby starburst galaxies NGC 2146 and NGC 3628.
18 stycznia 2018
prof. Joanna Mikołajewska (CAMK)
I will present and discuss recovery of the binary underlying the classical nova of 11 March 1437 recorded by Korean royal astronomers whose age is independently confirmed by proper motion-dating. I will also discuss the physical characteristics and the present evolutionary status of the binary system responsible for the nova outburst based on preliminary results of our ongoing extensive observations.
11 stycznia 2018
prof. Michał Ostrowski (OA UJ)
New gamma-ray observatories: Cherenkov Telescope Array (CTA)
4 stycznia 2018
dr Dagmara Oszkiewicz (IOA)
SANORDA (Service for Archival NEO Orbital and Rotational Data Analysis) is an ESA funded project aimed at archiving light curve and orbital data. In work package WP1200 we focus on determining historical orbits of all NEOs to reproduce their orbital improvement history starting from discovery onwards. The historical orbits may aid better observation planing and improve our understanding of astrometric biases present in the Minor Planet Centre database. We focus on two orbit computation methods: the ranging method and the traditional linearised least squares method. For asteroids with short observational arcs (shortly after discovery) we use ranging method and when the phase space of possible orbital solutions is sufficiently contained (close to Gaussian distribution) we switch to least squares. Those orbital histories are being reproduced for around 17 000 NEAs, which will result in almost 2 000 000 orbits. The project is ongoing and the final database is expected in 2018.
14 grudnia 2017
prof. Sławomir Breiter (IOA)
Poczwórny układ gwiazdowy w rezonansie 1:1
7 grudnia 2017
prof. Piotr Dybczyński (IOA)
O pochodzeniu międzygwiazdowego obiektu A/2017 U1
30 listopada 2017
dr hab. Tomasz Kwiatkowski (IOA)
A new catalogue of asteroid lightcurves
23 listopada 2017
dr Przemysław Bartczak (IOA)
Niepewności modeli planetoid
16 listopada 2017
prof. David Vokrouhlický (Astronomical Institute of Charles University, Prague)
Origin and evolution of short-period comets
9 listopada 2017
dr Krzysztof Kamiński (IOA)
Nowa poznańska kamera satelitarna
26 października 2017
dr Michał Michałowski (IOA)
Pierwsze obserwacje promieniowania wysyłanego przez zderzające się gwiazdy neutronowe – źródło fal grawitacyjnych
19 października 2017
dr Paweł Kankiewicz (IF UJK, Kielce)
Dynamika planetoid na orbitach wstecznych
12 października 2017
dr Anna Marciniak (IOA)
Pierścień wokół planety karłowatej Haumea oraz jej rozmiary, kształt i gęstość z obserwacji zakrycia gwiazdowego
Wystąpienia w roku akademickim 2016/2017:
8 czerwca 2017
mgr Mikołaj Krużyński (IOA)
Obserwacje sztucznych satelitów nie tylko przy użyciu PST2
1 czerwca 2017
dr Toni Santana-Ros (IOA)
Ménage à quatre projektów europejskich związanych z badaniem planetoid
25 maja 2017
mgr Krzysztof Langner (IOA)
Nowe podejście do transformacji Kustaanheimo-Stiefela
18 maja 2017
mgr Ewa Kosturkiewicz (IOA)
Badanie gwiazd pulsujących typu beta Cephei
11 maja 2017
dr Michał Michałowski (IOA)
Pył, galaktyki i błyski gamma
27 kwietnia 2017
mgr Patrycja Bagińska (IOA)
Nowe rentgenowskie: analiza i modelowanie rozbłysków
20 kwietnia 2017
mgr Magda Butkiewicz-Bąk (IOA)
Fotometria planetoid w gęstych polach gwiazdowych
6 kwietnia 2017
dr Anna Marciniak (IOA)
Fotometria, modelowanie i skalowanie planetoid o długich okresach i niskich amplitudach
30 marca 2017
prof. Tadeusz Jopek (IOA)
Spadek łańcuszkowy meteorytu Morasko
23 marca 2017
dr Magdalena Polińska (IOA)
Badania spektroskopowe gwiazd delta Scuti
16 marca 2017
prof. Witold Szczuciński (IG UAM)
Geologiczne i środowiskowe skutki małego uderzenia meteoroidu – wnioski z badań w rejonie Moraska
9 marca 2017
mgr Łukasz Gruszka (IOA)
Wyniki projektu LTDS związanego z dystrybucją czasu lokalnego
2 marca 2017
dr Krzysztof Kamiński (IOA)
Pakiet programów do planowania i redukcji obserwacji astrometrycznych Sztucznych Satelitów Ziemi
23 lutego 2017
dr Przemysław Bartczak, mgr Grzegorz Dudziński (IOA)
GAVIP-GC
dr Wojciech Dimitrow (IOA)
Relacja z “Warsztatów praktycznych ESO”
26 stycznia 2017
mgr Grzegorz Dudziński (IOA)
Status prac nad SAGE; inwersja obserwacji radarowych planetoid
12 stycznia 2017
dr Jerzy Nawrocki (OAG CBK PAN, Borowiec)
Uruchomienie fontanny cezowej w Borowcu
15 grudnia 2016
dr hab. Tomasz Kwiatkowski (IOA)
The olivine-dominated composition of the Eureka family of Mars Trojan asteroids
8 grudnia 2016
dr Krzysztof Kamiński (IOA)
Obserwacje SST za pomocą PST1 i PST2
24 listopada 2016
prof. David Vokrouhlický (Astronomical Institute of Charles University, Prague)
Tilting Saturn during planetary migration
17 listopada 2016
dr Jan Janik (Masaryk University, Brno)
Gorące gwiazdy w Brnie
10 listopada 2016
mgr Filip Berski (IOA)
Bliskie przejście gwiazdy Gliese 710
3 listopada 2016
dr Przemysław Bartczak (IOA)
Wyznaczanie kształtu planetoidy z krzywych zmian blasku i danych radarowych metodą SAGE
27 października 2016
dr Arkadiusz Hypki (Leiden Observatory)
MOCCA – current state and [Breiter] future ahead
20 października 2016
dr Dagmara Oszkiewicz (IOA)
Searching for parent bodies of anomalous HEDs
13 października 2016
dr Magdalena Otulakowska-Hypka (IOA)
Ciasne układy podwójne
6 października 2016
Michał Żołnowski, Grzegorz Duszanowicz, Marcin Gędek,
Michał Kusiak, Rafał Reszelewski (6ROADS)
Obserwacje SST i NEO przy pomocy sieci teleskopów 6ROADS
