The Andromeda Galaxy (/aenˈdrɒmɨdə/), ænˈdrɒmɨdə also known As messier, 31, m31 OR ngc, 224 is a spiral galaxy approximately 780 (kiloparsecs.2 5 million-light) years From. eartht 3.4, the apparent magnitude of the Andromeda Galaxy is one of the brightest of any of the Messier objects, making it visible to the naked eye on moonless nights even when viewed from areas with moderate light pollution.