25 research outputs found
HS Hya about to turn off its eclipses
Aims: We aim to perform the first long-term analysis of the system HS Hya.
Methods: We performed an analysis of the long-term evolution of the light
curves of the detached eclipsing system HS Hya. Collecting all available
photometric data since its discovery, the light curves were analyzed with a
special focus on the evolution of system's inclination. Results: We find that
the system undergoes a rapid change of inclination. Since its discovery until
today the system's inclination changed by more than 15 deg. The shape of the
light curve changes, and now the eclipses are almost undetectable. The third
distant component of the system is causing the precession of the close orbit,
and the nodal period is about 631 yr. Conclusions: New precise observations are
desperately needed, preferably this year, because the amplitude of variations
is decreasing rapidly every year. We know only 10 such systems on the whole sky
at present.Comment: 4 pages, 3 figures, published in 2012A&A...542L..23