The seven-year photobomb: Distant star’s dimming was likely a ‘dusty’ companion getting in the way, astronomers say

January 10, 2023 | UW News | James Urton

UW doctoral student Anastasios “Andy” Tzanidakis announced the discovery of a rare type of binary star system. Tzanidakis and Dr. James Davenport, a UW research assistant professor of astronomy and associate director of the DiRAC Institute, were investigating why the star Gaia17bpp had gradually brightened over a 2 1/2-year period. In some investigative follow-up work, which involved examining decades of observations of Gaia17bpp, they determined that the star itself was not changing. Instead, according to the data, Gaia17bpp is likely part of a rare type of binary star system, and its apparent brightening was the end a years-long eclipse by a stellar companion that is — quite simply — dusty. Gaia17bpp’s likely companion is slow-moving and surrounded by a disk of unknown material.

Catching this eclipse was a once-in-a-lifetime event, and indicates that this type of system may be more common than previously known. If so, scientists will need to develop theories of how such an unusual stellar pairing arose – because right now, that’s not easy to do.

Here is a link to the full story:

https://www.washington.edu/news/2023/01/10/dusty-binary/