If I say so myself, this is probably the best image of M31 (the Andromeda Galaxy) that I ever took. It’s made up from about 2 1/2 hours of one minute images using my 11″ SCT at f/1.9 with my ZWO ASI294MC Pro camera at a gain setting of 120. Full disclosure: I nuked two satellite galaxies in the processing of this image as they were not looking good. That’s okay since this is art not science.
M31 is possibly the farthest object visible to the unaided eye at 2.5 million light years away. I say possibly because another galaxy, M33 is slightly further away and can be glimpsed in very dark skies. But that is a story for another time, this is about M31.
M31 was first described in 964AD by a Persian astronomer who recognized its “fuzziness”. Until about 100 years ago, this was called the Andromeda Nebula. Then, in 1925, Edwin Hubble (of space telescope fame) used the then largest telescope in the world to identify and measure specific stars in the nebula and realized just how far away the object is. Until recently, M31 was thought to be as much as 50% larger than our own Milky Way galaxy. Recent measurements though have shown that the Milky Way is actually somewhat larger.
