A local stellar graveyard could reveal our galaxy’s beginnings
Artist’s impression of the thin stream of stars torn from the Phoenix globular cluster, wrapping around the Milky Way (left). Astronomers targeted bright red giant stars (artist’s impression, right) to measure the chemical composition of the disrupted Phoenix globular cluster. (James Josephides, Swinburne Astronomy/)Some two billion years ago, the Milky Way scarfed down a ball of about a million stars until the gravitational pull of our galaxy tore it into a 27,000-light-year-long stellar river. Now, new research looking at the gobbled up remains of our galaxy’s snack suggest that it wasn’t born in our corner of the universe—and these unique origins could help us understand the early assembly of the Milky Way.The unusual collection of stars—dubbed the “Phoenix stream,” after the constellation in which it’s visible—is what’s known as a stellar stream: an elongated chain of stars that used to be a globular cluster, a densely packed swarm of ancient...