Marissa Gebhard | June 20 2016
No one has yet observed the first stars that formed in the Milky Way. In all likelihood, they will never be directly observed, because the first stars are massive, ending their lives only a few millions years after their birth.
But, astronomers can study those oldest stars by examining the elements these stars produced through nuclear fusion and the supernova explosions that mark the spectacular ends of their short lives.
Timothy Beers, the Notre Dame Chair in Astrophysics at the University of Notre Dame, is part of a team that has used the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope to study key regions of the ultraviolet (UV) spectrum of a star thought to have been enriched by elements from one of the first generation of stars. This star, named BD+44 493, is the brightest known second-generation star in the sky. While examining its UV spectrum, Beers and his team detected several elements that had never been seen before in such a star. Their findings were published Monday (June 20) in the Astrophysical Journal Letters.