Page 512 - AWSAR 2.0

488 || AWSAR Awarded Popular Science Stories - 2019
A Sign of Three: Puzzle of an Unseen Body in Contact Binary Stars
Email: malu.sudhaj@gmail.com
Ms. Malu S.*
What do we see when we look up at the night sky? What is out there? And what is our place in this beautiful, mysterious universe?
These were, perhaps, some of the elementary questions that drove humanity to study the stars. From simply staring at the vastness of space from the grounded reality of primitive earthly life, and naming constellations in the heavens, we moved on to create better and better technology to study the cosmos. And much to the credit of our still young species, we have made many a leap of progress in this venture.
In the last decades, much to the fascination of astronomers, it was discovered that a significant fraction of stars existed as part of binary systems, that is, in pairs. Furthermore,
around 10%–20% of stars seem to exist in triple systems, whose evolution continues to be heavily debated in the scientific community.
The laws of Kepler, which are about the motion of two bodies around a common centre of mass, become a matter of interest here. These binary systems also provide an excellent opportunity to study the masses, radii and temperatures of the stars in them. Only upon having that knowledge can we predict their fate.
Scientists can analytically measure the mass of stars in such binary or triple systems, but not of lone stars.
Evolution hangs upon how much of each star’s mass and angular momentum are lost over time. Orbital periods of binary stars are found to be either increasing or decreasing,
* Ms. Malu S., PhD Scholar from Department of Astronomy, Osmania University, Telangana, is pursuing her research on “X-Ray and Optical Studies of Mass Accreting Binary Systems using ASTROSAT and GroundBased Observatories”. Her popular science story entitled “A Sign of Three: Puzzle of an Unseen Body in Contact Binary Stars” has been selected for AWSAR Award.