Lawrence Molnar et al

Science Track: Lawrence Molnar, Michaela Blain, Sarah Whitten and Lauren Henderson, Calvin University, Physics and Astronomy: “Bowling Pins in Space"

A contact binary star is a system of two stars that orbit each other so closely that they share a common outer atmosphere. Due to tidal elongation and rotation, they are shaped more like a bowling pin than two balls glued together. They are the most common type of eclipsing binary stars yet the details of their formation, evolution, and demise are poorly understood. In the past few years, our research group has developed the first comprehensive theory of contact binary star evolution. Our theory includes formation catalyzed by the presence of a third star, evolution driven by gradual cannibalism of the smaller star, and death via an explosive merger. We will discuss the ways in which we have tested these ideas against the observations in the largest catalog of variable stars to date and what further tests are needed.