The Andromeda galaxy, also known as M31, and the Triangulum galaxy, or M33, may have brushed closely billions of years ago, new observations indicate. Artist’s impression of a gas bridge between M31, right, and M33 (Bill Saxton / NRAO / AUI / NSF) The observations, presented today at the American Astronomical Society’s meeting in Anchorage, Alaska, confirm a disputed 2004 discovery of hydrogen gas streaming between two of Milky Way’s...
