This is M31, the Andromeda Galaxy. Andromeda is our closest neighboring galaxy. In fact, we are getting closer all the time. Scientists predict that our galaxy, the Milky Way, will eventually collide with Andromeda. When that happens, there is actually a chance that our solar system could be "captured" by Andromeda -- we could actually swap galaxies! We won't know for sure for a few million years, but place those bets early.
Another interesting fact about Andromeda and its distance and size... Since light takes time to travel through the universe, the further distances we see, the "older" the light is. In other words, if we look at an object that is 100 light years away we are actually seeing light that is 100 years old -- we are seeing that object as it was 100 years ago. Hence, we are looking into the past.
The light traveling from the far side of Andromeda left before man ever walked the Earth, while the light on the near side of Andromeda left after the first recorded history. So, Andromeda is also an amazing "time line" of man's existence. Pretty cosmic, huh?
Anyway, I took this image last October at Rancho Venado. I had a couple of false starts, but finally was satisfied with this image (I haven't done too many galaxies yet). It was taken with the FSQ 106ED with a total exposure of 110 minutes.
Happy holidays!