Astronomers home in on offspring of universe ’s first stars

The universe’s very first stars were giants that burned fast and died young in spectacular explosions. They may never be spotted directly—although NASA’s James Webb Space Telescope, which by looking far away can see back to the times when they were shining , may get lucky. In the meantime, astronomers may have discovered the next best thing: a descendant, born from the wreckage of a first-generation star, that has been quietly shining near the Milky Way ever since. A closer inspection, and finding more descendants like it, could clue researchers into how big the first stars were and how they affected the universe’s evolution. “We’re trying to do forensic analysis of objects that blew up 13.5 billion years ago. They’re just not there anymore,” says astronomer Timothy Beers of the University of Notre Dame, who was not involved in the study. “If this is a pure [descendant], that puts very strong constraints” on the masses of the first stars. Theorists believe that first-generation stars, known as population III, were made of only the ingredients left over from the big bang, mostly hydrogen and helium. As they burned, they fused those ingredients into heavier elements that astronomers lump together as “metals.” When the stars exploded as supernovae after lifetimes as short as a few million years, the metals spread out and mixed with more hydrogen and helium in later generations of stars. The limited ingredients in population III...
Source: Science of Aging Knowledge Environment - Category: Geriatrics Source Type: research