UW News
Melissa Graham
January 10, 2019
Astronomers find signatures of a ‘messy’ star that made its companion go supernova
![An image of a galaxy in outer space, with a bright supernova visible at its outer edge.](https://uw-s3-cdn.s3.us-west-2.amazonaws.com/wp-content/uploads/sites/6/2019/01/04160226/SN1994D_NGC4526_web-150x150.jpg)
On Jan. 10 at the 2019 American Astronomical Society meeting in Seattle, an international team of astronomers announced that they have identified the type of companion star that made its partner in a binary system, a carbon-oxygen white dwarf star, explode. Through repeated observations of SN 2015cp, a supernova 545 million light years away, the team detected hydrogen-rich debris that the companion star had shed prior to the explosion.