Astronomers taking a close look at our nearest neighbor galaxy have made a highly unusual and model-challenging discovery; ...

Our neighboring Andromeda Galaxy (Messier 31, or M31) appears to sport a lopsided arrangement of satellite galaxies that defy ...

Spanning approximately 220,000 light-years across, the Andromeda Galaxy is the largest galaxy of the Local Group, which also ...

called the Andromeda Nebula (after the constellation in which it was located). It was entry 31 in Charles Messier's 18th century catalog of interesting fuzzy objects, and is thus also called M31 ...