Weekly seminars 2018/2019
Our weekly seminars take place on Thursdays at 1:00 p.m. in AMU Astronomical Observatory building at 36 Słoneczna Street. The person responsible for organization of seminars is Dr Tomasz Kwiatkowski, to whom all questions regarding dates/subjects, as well as the video equipment needed should be directed.
4th October 2018
Administrative matters
11th October 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?
18th October 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.
25th October 2018
prof. Tadeusz Jopek (IOA)
We have made an extensive search for grouping amongst the near Earth asteroids (NEAs). We used two D- functions and rigorous cluster analysis approach. We have found several new groups (associations) among the NEAs: the objects moving on similar orbits with small minimum orbital intersection distances (MOID) with the Earth trajectory.
8th November 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.
15th November 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.
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22nd November 2018
29th November 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.
6th December 2018
dr Arkadiusz Hypki (IOA)
13th December 2018
dr Krzysztof Hełminiak (CAMK PAN)
High-resolution spectroscopic survey of Kepler detached eclipsing binaries
20th December 2018
mgr Aleksandra Leśniewska (IOA)
10th January 2019
prof. Vasilij Shevchenko (Karazin Kharkiv National University, Ukraine)
17th January 2019
mgr Piotr Guzik (OA UJ)
24th January 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.
31th January 2019
dr Edyta Podlewska-Gaca (IOA)
New models of Asteroids from the projects SBNAF and Large Programme VLT
28th February 2019
mgr Ewa Kosturkiewicz (IOA)
7th March 2019
mgr Volodymyr Troiansky (IOA)
14th March 2019
mgr Patrycja Bagińska (IOA)
21th March 2019
mgr Mikołaj Krużyński (IOA)
Previous talks:
21st June 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.
14th June 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.
7th June 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.
24th May 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.
17th May 2018
mgr Ewa Kosturkiewicz (IAO)
Spectroscopic observational campaign of the delta Ceti star in 2014 – 2017 – preliminary results
10th May 2018
mgr Krzysztof Langner (IAO)
Kustaanheimo-Stiefela (KS) transform is used to regularize and linearize Kepler problem and t transform it into harmonic oscillator. Regularization changes the independent variable (time) and can improve accuracy of numerical propagation of orbits, especially when eccentricity is high. Lissajous variables are used as action-angle variables for harmonic oscillator. In my presentation I will show these two transforms using canonical formalism and extension for orbits with explicit time dependent perturbation.
26th April 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.
19th April 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.
12nd April 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.
5th April 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.
22nd March 2018
prof. Agnieszka Kryszczyńska (IAO)
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.
15th March 2018
Seminar canceled
8th March 2018
prof. Edwin Wnuk (IAO)
In December 2017 Polish Space Agency announced the National Space Programme
(KPK) for Poland. After concultations with all interested parties KPK
shall be accepted in the first quarter of 2018. Next the first calls
shall be announced covering a broad range of space studies, including
astronomical reserach.
Quadruple stellar system in the 1:1 resonance
During the talk three highest priority KPK projects shall be presented as
well as the areas in which the first calls for grant proposals shall be
announced. Guidelines for grant applications as well as the planned KPK
budget shall be discussed.
1st March 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.
22nd February 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.
25th January 2018
Dr An-Li Tsai (IAO)
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.
18th January 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.
11th January 2018
Prof. Michał Ostrowski (OA UJ)
New gamma-ray observatories: Cherenkov Telescope Array (CTA)
4th January 2018
Dr Dagmara Oszkiewicz (IAO)
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.
14th December 2017
Prof. Sławomir Breiter (IAO)
Quadruple stellar system in the 1:1 resonance
7th December 2017
Prof. Piotr Dybczyński (IAO)
On the dynamical history of the recently discovered interstellar object A/2017 U1
30th November 2017
Dr Tomasz Kwiatkowski (IAO)
A new catalogue of asteroid lightcurves
23rd November 2017
Dr Przemysław Bartczak (IAO)
Asteroid models uncertainty
16th November 2017
Prof. David Vokrouhlický (Astronomical Institute of Charles University, Prague)
Origin and evolution of short-period comets
9th November 2017
Dr Krzysztof Kamiński (IAO)
New satellite tracking camera in Poznań
26th October 2017
Dr Michał Michałowski (IAO)
The first observation of radiation from colliding neutron stars – the sources of gravitational waves
19th October 2017
Dr Paweł Kankiewicz (Jan Kochanowski University, Kielce)
Dynamical studies of asteroids in retrograde orbits
12th October 2017
Dr Anna Marciniak (IAO)
The size, shape, density and ring of the dwarf planet Haumea from a stellar occultation
Talks in 2016/2017:
8th June 2017
Mikołaj Krużyński (IAO)
SST observations – not only with PST2
1st June 2017
Dr Toni Santana-Ros (IAO)
A ménage à quatre of European projects linked by the study of asteroids
25th May 2017
Krzysztof Langner (IAO)
New approach to Kustaanheimo-Stiefel transform
18th May 2017
Ewa Kosturkiewicz (IAO)
Study of beta Cephei-type pulsating stars
11th May 2017
Dr Michał Michałowski (IAO)
Dust, galaxies and gamma ray bursts
27th April 2017
Patrycja Bagińska (IAO)
X-ray novae: analysis and modelling of outbursts
20th April 2017
Magda Butkiewicz-Bąk (IAO)
Photometry of asteroids in crowded star fields
6th April 2017
Dr Anna Marciniak (IAO)
Photometric survey, modeling and scaling of long-period and low-amplitude asteroids
30th March 2017
Prof. Tadeusz Jopek (IAO)
The Morasko meteorite chain fall
23rd March 2017
Dr Magdalena Polińska (IAO)
Spectroscopic study of delta Scuti stars
16th March 2017
Prof. Witold Szczuciński (Institute of Geology, Adam Mickiewicz University)
Geological and environmental effects of small hypervelocity meteoroid impacts – insights from Morasko impact
9th March 2017
Łukasz Gruszka (IAO)
Legal Time Distribution System: a technique for transfering accurate time
2nd March 2017
Dr Krzysztof Kamiński (IAO)
Software tools for planning and reduction of astrometric observations of Earth’s Artificial Satellites
23rd February 2017
Dr Przemysław Bartczak, Grzegorz Dudziński (IAO)
GAVIP-GC
Dr Wojciech Dimitrow (IAO)
A report from ESO workshop
26th January 2017
Grzegorz Dudziński (IAO)
SAGE development status; invertion of asteroids’ radar echo observations
12th January 2017
Dr Jerzy Nawrocki (OAG CBK PAN, Borowiec)
Caesium fountain in Borowiec
15th December 2016
Dr Tomasz Kwiatkowski (IAO)
The olivine-dominated composition of the Eureka family of Mars Trojan asteroids
8th December 2016
Dr Krzysztof Kamiński (IAO)
SST observations with PST1 and PST2
24th November 2016
Prof. David Vokrouhlický (Astronomical Institute of Charles University, Prague)
Tilting Saturn during planetary migration
17th November 2016
Dr Jan Janik (Masaryk University, Brno)
Hot stars in Brno
10th November 2016
Filip Berski (IAO)
Close approach of Gliese 710
3rd November 2016
Dr Przemysław Bartczak (IAO)
SAGE: modelling asteroid shapes based on light curves and radar data
27th October 2016
Dr Arkadiusz Hypki (Leiden Observatory)
MOCCA – current state and [Breiter] future ahead
20th October 2016
Dr Dagmara Oszkiewicz (IAO)
Searching for parent bodies of anomalous HEDs
13th October 2016
Dr Magdalena Otulakowska-Hypka (IAO)
Close binary stars
6th October 2016
Michał Żołnowski, Grzegorz Duszanowicz, Marcin Gędek,
Michał Kusiak, Rafał Reszelewski (6ROADS)
SST and NEO observations with 6ROADS telescope network
