Variable Stars

Fraom article Sturm/Schwab SuW 1982

Nava Aquilae 1982 lightcurve. From article Sturm/Schwab, SuW 1982

Already in the 1980th I observed variable stars at the Starkenburg Observatory Heppenheim, see articles of Nova Aquilae from german magazine Sterne und Weltraum (1982) and the german newspaper (1985).

Almost four decades later, on 2019-07-26, I tried to recover Comet P/2012 K3 (Gibbs) with the Calar Alto Schmidt Telescope (funded by ESA) and discovered randomly the variability of the star USNO-B1.0 0735-0599207. After the discovery was accepted the object got the AAVSO Unique Identifier 000-BNG-512 and I found out (mentored by Ulrich Bastian, Heidelberg) that it is one of the rare cataclysmic variables of DQ Herculis type. Together with Paul Breitenstein the orbital- and spin periods have been precisely determined, for which we received the „Samuel Thomas von Soemmerring-Award 2020“ of the Physical Society at Frankfurt am Main, Germany.
-> Entry in the International Variable Star Index (VSX) discovery independent to PanStarrs*
*PanStarrs Team has incorrectly determined the period and also not correct classified it as RR-Lyrae type
-> Publication of periods determinations in BAV-Rundbrief #68, December 2019 (in German) together with Paul Breitenstein
-> A summary used as poster for  Award ceremony (in German)

Since 2020 I am registered observer (individual code EERA) of the American Association of Variable Star Observers (AAVSO).  The following lightcurves I have submitted to the database of the AAVSO:
-> 000-BNG-512 on 2020-05-25  cataclysmic DQ Herculis type, dwarf star rotation recorded
-> EP Dra             on 2020-05-30  cataclysmic AM Herculis type, eclipsing recorded