Birth of a Blue Straggler Star

[Left] - A normal star in a binary system gravitationally pulls in matter from an aging companion star that has swelled to a bloated red giant that has expanded to a few hundred times its original size.

[Right] - After a couple hundred million years, the red giant star has burned out and collapsed to the white dwarf that shines intensely in ultraviolet wavelengths. The companion star has bulked up on the hydrogen siphoned off of the red giant star to become much hotter, brighter, and bluer than it was previously.

About the data

These data were obtained via the HST proposal GO: 12492 , PI: R. Mathieu (University of Wisconsin, Madison) et al.

The science team comprises: N. Gosnell (University of Texas, Austin), R. Mathieu (University of Wisconsin, Madison), A. Geller (Northwestern University and University of Chicago), A. Sills (McMaster University), N. Leigh (University of Alberta and American Museum of Natural History), and C. Knigge (University of Southampton, UK).