Astronomers from the University of Washington, Western Washington University and the University of California, Irvine have recorded the actions of a binary system of stars that bend each other’s motions in space.
This system is called eclipsing binary, or binary eclipse. From Earth, it seems that two stars are passing over each other or overshadowing each other. This happens because they rotate around a common center of gravity, alternately closing each other. Such eclipses cause the amount of light emitted by the binary system to periodically decrease.
We have documented the full rise and fall of this binary star.
James Davenport, Associate Professor of Astronomy at Washington State University and Associate Director of the DIRAC Institute
Such systems are rare, according to Davenport, and today scientists only know about 12 of them. In order to document the entire action of the stars, scientists observed them and looked for long-term changes.
The system of two stars was called HS Hydra, it is 342 light-years from us, it is a relatively close and bright system, where stars orbit each other every 1.5 days. Scientists first discovered it in 1965.
Davenport and his team monitored the system using the NASA Transiting Exoplanet Survey Satellite, or TESS. They observed that the system was reduced in brightness by only 0.0075 magnitude from HS Hydra, which means that the stars almost did not cover each other during eclipses.
The team predicts that the HS Hydra eclipses will end around February 2021.