2013 – Roztoky 12 – 21 August


Name/ MenoSurname/ PriezviskoAffiliation/ OrganizáciaResearch task/ Výskumná úloha
MariannaHronovskáZŠ Smižany1. Extinction Coefficients
ErykLipkaUniversity of Warsaw3. Semiregular and Symbiotic variable stars
MałgorzataCuryłoJagellonian University Krakow5. Superhumps
BartłomiejDębskiJagellonian University Krakow5. Superhumps
MarcinKlimaszewskiJagellonian University Krakow5. Superhumps
FilipPajakII High School DEBICA7. Cepheids
MateuszZajchowskiI LO Krosno7. Cepheids
MatušKamenecZŠ Lesnícka, PO8. The accuracy of visual observations
RadoslavNovysedlákSAS pri SAV, SZA, AKB8. The accuracy of visual observations
IgorKudzejVihorlatská hvezdáreňHEAD
DanielBaluďanskýHvezdáreň RoztokyOPERATOR
JánSadivHvezdáreň RoztokyOPERATOR
PavolDubovskýVihorlatská hvezdáreňSUPERVISOR



The astrocamp was organized by the Vihorlat Observatory in cooperation with the Podduklianske Educational Centre in Svidník at the observatory in Roztoky. The originally planned date had to be slightly postponed due to organizational reasons. The event took place from 12 to 21 August 2013. Observation activities in the second part of the astrocamp were therefore disturbed by the waxing Moon. However, the educational nature of astrocamp was not hindered, quite the opposite. At Variable, astronomers, amateurs, students and all those interested in research of variable stars deal mainly with practical astronomy, i.e. by various photometric methods. The goal is to exchange experience, learn new techniques, enrich theoretical knowledge. This goal was fully fulfilled by astrocamp in Roztoky.

The Variable astrocamp takes place as a game for real scientific research. Participants are researchers who solve specific tasks that they chose when applying. They rely on cooperation with consultants who guide them theoretically and technicians who ensure the correct operation of the observation instruments. In Roztoky, Pavol A. Dubovský from the Vihorlat Observatory acted as a consultant. The technician was Daniel Baluďanský, an employee of the observatory in Roztoky. The main leader of the expedition was RNDr. Igor Kudzej, CSc. from the Vihorlat Observatory in Humenne.

From the eight tasks offered, participants chose the following five:

1. Extinction – Solved by Marianna Hronovská, teacher of mathematics and physics at primary school in Smižany. From the archival data of the Astronomical Observatory at Kolonica Saddle, she determined the extinction coefficients of the first order for photometric filters V and Rc. She used all-night run observations of the variable star BG CMi. It is clear from the solution of the task that such a method of determining extinction coefficients is applicable only if the atmosphere is stable throughout the night. An alternative method based on observations of different stars at different heights above the horizon with a photoelectric photometer at almost the same time will be tried an astrocamp in the future.

3. Semiregular variables and symbiotic – Selected variables from the program of the Czech group Medusa were observed visually by Eryk Lipka from the University of Warsaw through 20 cm Dobsonian telescope. But not only him. The magic of this tasks game lies in the fact that the solver should bring other participants of the astrocamp to make visual estimates. In this case the solvers of task no. 8 were involved. A total of 92 visual estimates were collected and submitted to the AAVSO and Medusa database.

5. Superhumps – A group from the Jagiellonian University in Krakow, led by regular Variable participant Bartlomej Debski, focused on a dwarf nova of the SU UMa type, which flared up during the astrocamp. It was a newly discovered object ASAS J224349+0809.5. After initial problems with the technology, it was possible to observe 4 nights using a 25 cm diameter Newton telescope on the EQ6 mount and a G2-1600 CCD camera unfiltered. The results are brilliantly described in the final presentation. However, they only gained real significance in conjunction with other observations collected from around the world by Taichi Kato of the University of Kyoto within the VSNET network. This is evidenced by vsnet-alert no. 16257.

7. Cepheids – another task based on visual observations was solved by Filip Pajak from the lyceum in Debica and Mateusz Zajchowski from the lyceum in Krosno. Their target were the most famous cepheids Delta Cep and Eta Aql. They combined their observations on the astrocamp with visual observations of one observer from the Medusa database and tried to determine the period. In the case of Delta Cep, the periodogram was really impressive. On future astrocamps, it would be worth analyzing in more detail the accuracy of determining the distance of cepheids based on visual observations using the well-known empirical period-luminosity relationship.

8. Accuracy of visual observations – The experiment with observation of constant stars was carried out by Matúš Kamenec (Elementary School Lesnícka, Prešov) and Radoslav Novysedlák (Slovak Union of Astronomers). For this purpose, they used customized maps around the variable stars SS Cyg and V840 Cyg. They used two telescopes: 15 cm Schmidt-Cassegrain on the GoTo mount and a 15 cm refractor in the observatory’s sliding house. Other participants were quite reluctant to participate in the experiment. Thus, not enough data was collected for the relevant statistical conclusions. However, it became clear that minor deviations were achieved by observers in the case of the V840 Cyg array. This can be explained by the fact that the brightness scale in this case was more densely covered by comparison stars, and also by the fact that the stars in the field had smaller differences in color indices. This would confirm the assertion of experienced visual observers that a high-quality map is needed above all to obtain a quality measurement.

The atmospheric conditions of the astrocamp were extremely favorable. Practical observations were made on all nights except the first and last. This is absolutely the ideal model. The theoretical part was therefore limited. Nevertheless, interesting lectures were given by B. Debsky on the research of hot subdwarfs, P. A. Dubovsky on superhumps in light of the data from the Kepler mission, D. Baluďanský about the history and present of the observatory in Roztoky. Also, the sports part of the astrocamp was limited. There was one small tennis tournament, several hiking trips and two visits to swimming pools. On Saturday, August 17, astronomy was also promoted at the swimming pool in Svidník. During the day, we showed signs of solar activity through a solar telescope, and during night bathing also the Moon and Saturn.

Thanks for the flawless logistical provision of the astrocamp belongs to the Podduklianske Educational Centre in Svidník, headed by the director PhDr. Maria Pajzinková and employee Daniel Baluďanský, who accompanied the entire astrocamp as a technician.