Milky Way seen snacking on river of stars

U.S. astronomers say they've observed a band of stars believed to be the remnant of an ancient star cluster slowly being ingested by our Milky Way galaxy. "The Milky Way is constantly gobbling up small galaxies and star clusters," lead study author Ana Bonaca, a Yale graduate student, said. "The more powerful gravity of our Milky Way pulls these objects apart and their stars then become part of the Milky Way itself." While previous studies have found evidence of the Milky Way having a cosmic snack of dwarf galaxies, the researchers argue the newly found stellar stream is the remnant of a star cluster rather than of a larger galaxy because the stream is very narrow, a Yale release said Thursday. "Our discovery is more of a light snack than a big meal for the Milky Way," co-author Marla Geha, a Yale professor of astronomy, said. "Studying this digestion process in detail is important because it gives us new insight into how all galaxies form and evolve." Named the Triangulum stream, the newly discovered river of stars could also help reconstruct how the Milky Way's mass is distributed, further revealing its dynamic structure, astronomers said.