I’m excited to pop up here on the European Interferometry Initiative (EEI) page:

https://european-interferometry.eu/a/?loose=14&l2title=un-women-in-science-2026 .

Take a look!

It’s a place where teams across Europe join forces to push optical long‑baseline interferometry forward, mixing expertise from different institutes and labs. It feels great to land in a space that’s all about collaboration and exploring the limits of high‑resolution astronomy.

And today makes it feel even more special, because it’s the International Day of Women and Girls in Science — a day that highlights how important it is to support women in STEM. With women still making up less than one third of researchers worldwide, this celebration is both a reminder and a motivation to keep pushing for more balance and more opportunities.

So I’m happy to join in, add my little spark to this community, and celebrate a day that encourages more women to take up space in science. Here’s to more voices, more ideas, and more of us shaping the future of astronomy — one observation at a time and one small step (or interferometric baseline) at a time.

It’s been a while, hasn’t it?

Somehow a few years slipped by, filled with some new projects, papers, conferences, teaching, unexpected adventures, and a handful of students who bravely survived the journey to graduation.

And now - here I am again.

I’ve missed having this little corner of the internet, so I’m officially dusting it off.

New posts are coming, slowly but surely. I’m excited to share what I’ve been working on, what I’ve learned, and probably a few things I’m still figuring out.

Stay tuned - more soon!

Polish National Science Centre (NCN) has awarded me the SONATINA 3 grant!

Here is the official information, and here you can find the news on the website of my Institute.

During the next three years I am going to study symbiotic stars with the use of optical interferometry. Finally! I've been waiting for such opportunity for quite a long time. A description of the project for the general public can be found here. For more information, please, don't hesitate to contact me.

So, stay tuned for hopefully exciting news coming from this project in the near future!

Between 14th and 16th Nov. 2018 I participated in the Advances with SALT Conference in Pretoria, South Africa.

The conference covered recent SALT scientific achievements as well as upcoming projects and the strategic plans for the future of SALT. In addition to contributed presentations, there were also many less formal sessions and discussions, which were especially fruitful from my personal point of view.

Today at the Astronomical Observatory of Kościan I gave a popular talk: How can we measure the size of a coin located on the Moon from the Earth?

Observations in astronomy are the basic source of information. Over the centuries, the methods of conducting such observations, as well as their reduction and analysis, have undergone tremendous evolution, and in recent years even a revolution. Currently, the latest technical developments combined with the basic laws of physics let us recognize the unprecedented details of celestial bodies. For example, even those with the size of a coin seen from Earth on the Moon. I introduced these methods of observations and presented their applications to modern astronomy.

The direct answer to the question in the title is of course: with the use of optical interferometry. And that was the main topic of my talk.

Fig. The Astronomical Observatory of Kościan

From the 9th to the 14th of July in Lisbon, Portugal, I participated in the 9th VLTI Summer School organised by the Portuguese VLTI Expertise Centre, the JMMC, the EII, and ESO.

The school was set to train the VLTI users. It was very practical and we were introduced to the tools used in observation preparation and VLTI data reduction. In particular, to the newest GRAVITY instrument, but also others, like AMBER, PIONIER, and of course MATISSE. For me, personally, the new generation of VLTI instruments was the most interesting because it was new to me. Over this intense week we have learned a lot and on Friday all the participants presented their VLTI proposals to everybody present. It was a very educative experience!

Last but not least, during the week I met a lot of interesting and joyful astronomers and I really enjoyed our time in Lisbon and Belém ;)

Now, it is time to make use of all the new VLTI skills!

Today my Master student - Aleksandra Leśniewska - defended her Master Thesis Modeling of symbiotic star SY Mus based on photometric and spectroscopic observations with the best mark!

I'm so proud :)

Our article has just been accepted by Astronomy & Astrophysics: LINK.

The work entitled "Testing the disk instability model of cataclysmic variables" was led by Guillaume Dubus (Univ. Grenoble Alpes, CNRS, Grenoble, France), in co-operation with Jean-Pierre Lasota (Institut d'Astrophysique de Paris, CNRS and Sorbonne Université, Paris, France and N. Copernicus Astronomical Center, Warsaw, Poland), and myself.

The disk instability model (DIM) was introduced by Meyer & Meyer-Hofmeister (1981), Smak (1984), Cannizzo (1993), and Lasota (2001). It 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.

Figure 1. One way to show DIM on a plot is the orbital period (Porb) vs. mass transfer rate (Mdot) dependence, as this theoretical one from Osaki (1996). The dashed line is the border between the thermally stable and unstable disks. NL (nova-likes) and PS (permanent superhumpers) are located in the thermally stable region, as opposed to dwarf novae: SU (SU UMa stars) and their sub-classes, ER (ER UMa) and WZ (WZ Sge) stars, as well as UG (U Gem) and ZC (Z Cam) systems.

Our aim was to test the fundamental prediction of the DIM: the separation of cataclysmic variables (CVs) into nova-likes and dwarf novae (DN) depending on orbital period and mass transfer rate from the companion. In the past it has been done only twice, with a very sparse set of data (Smak, 1982, and Schreiber & Lasota, 2007). This time we test the DIM for a LARGE NUMBER of CVs. We analyzed the light curves from a sample of ≈130 CVs with a parallax distance in the Gaia DR2 catalog to derive their average mass transfer rate. We validated the method for converting optical magnitude to mass accretion rate against theoretical light curves of dwarf novae.

Our result is in a wonderful agreement with the DIM predictions!

Figure 2. Our results: mass transfer rates: calculated and critical. NL in red, DN in grey.

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 DIM. 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 basis on which to construct an understanding of accretion processes in CVs.

For details, see: LINK.

On 7th June, 2018, I gave a seminar talk at our Institute Astronomical Observatory of Adam Mickiewicz University in Poznań: LINK.

During the talk I presented my recent publication Testing the disk instability model of cataclysmic variables (Dubus et al. 2018) which is described here: LINK.

Although the topics related to cataclysmic variables are not very popular at my Institute, I try to bring an interest of our students to this subject.

Our proceedings from the XXXVIII Polish Astronomical Society Meeting held 11-14 September, 2017, in Zielona Góra, Poland, has been published: LINK.

We studied an eclipsing symbiotic system composed of a white dwarf and a red giant, SY Mus. With the use of observational data in the infrared bands within the PHOEBE software, we determined physical parameters of the system, such as masses and radii.

This work was led by my Master student - Aleksandra Leśniewska, who presented there the preliminary results of our SY Mus study which will be a base of her Master thesis this year.
It has been done in co-operation with Prof. Joanna Mikołajewska (N. Copernicus Astronomical Center, Warsaw, Poland) and Prof. Patricia A. Whitelock (SAAO and Astronomy, Cosmology and Gravity Centre, Astronomy Department, University of Cape Town, South Africa).

Fig. Our model of SY Mus.

I'm finishing my maternity leave today! Big day for all of us :)

We are happy to announce that our recent paper entitled

Statistical analysis of properties of dwarf novae outbursts

by Magdalena Otulakowska-Hypka (Sterrewacht Leiden), Arkadiusz Olech (N. Copernicus Astronomical Center), and Joseph Patterson (Columbia University) has been accepted for publication in Monthly Notices of the Royal Astronomical Society.

In this work we present a statistical study of all measurable photometric features of a large sample of dwarf novae during their outbursts and superoutbursts. We used all accessible photometric data for all our objects to make the study as complete and up-to-date as possible. Our aim was to check correlations between these photometric features in order to constrain theoretical models which try to explain the nature of dwarf novae outbursts. We managed to confirm a few of the known correlations, that is the Stolz and Schoembs Relation, the Bailey Relation for long outbursts above the period gap, the relations between the cycle and supercycle lengths, amplitudes of normal and superoutbursts, amplitude and duration of superoutbursts, outburst duration and orbital period, outburst duration and mass ratio for short and normal outbursts, as well as the relation between the rise and decline rates of superoutbursts. However, we question the existence of the Kukarkin-Parenago Relation but we found an analogous relation for superoutbursts. We also failed to find one presumed relation between outburst duration and mass ratio for superoutbursts. This study should help to direct theoretical work dedicated to dwarf novae.

The publication can be already found on the NASA Astrophysics Data System: http://adsabs.harvard.edu/abs/2016arXiv160502937O or downloaded from the arXiv: http://arxiv.org/abs/1605.02937 or MNRAS: http://mnras.oxfordjournals.org/content/early/2016/05/12/mnras.stw1120; the doi number is: 10.1093/mnras/stw1120.

The corresponding catalog is accessible on my old website: http://users.camk.edu.pl/magdaot/DN.html

Please, use it, share it, and enjoy!

The project was supported by Polish National Science Center grant awarded by decision number DEC-2011/03/N/ST9/03289.