New research provides the best evidence to date into the timing of how our early Milky Way came together, including the merger with a key satellite galaxy.
Using relatively new methods in astronomy, the researchers were able to identify the most precise ages currently possible for a sample of about a hundred red giant stars in the galaxy.
With this and other data, the researchers were able to show what was happening when the Milky Way merged with an orbiting satellite galaxy, known as Gaia-Enceladus, about 10 billion years ago.
Their results were published today (May 17, 2021) in the journal Nature Astronomy.
“Our evidence suggests that when the merger occurred, the Milky Way had already formed a large population of its own stars,” said Fiorenzo Vincenzo, co-author of the study and a fellow in The Ohio State University’s Center for Cosmology and Astroparticle Physics.
Many of those…