An Amazing Image,

from out of space, 

(Image credit: NASA, ESA, Benjamin F. Williams (UWashington), Zhuo Chen (UWashington), L. Clifton Johnson (Northwestern); Image Processing: Joseph DePasquale (STScI)), (Image credit: NASA, ESA, Benjamin F. Williams (UWashington), Zhuo Chen (UWashington), L. Clifton Johnson (Northwestern); Image Processing: Joseph DePasquale (STScI)), it took 10 years, 1,000 Hubble orbits, and required over 600 overlapping images to complete the Andromeda galaxy with, wait for it, over 2.5 billion pixels, from the article:

'The magnificent Andromeda galaxy (Messier 31), stands out as the most important nearby stellar island to our Milky Way, and can be seen with the naked eye on a clear autumn night as “a faint cigar-shaped object roughly the apparent angular diameter of our Moon” according to NASA. The telescope's namesake, American astronomer Edwin Hubble (1889 - 1953), first discovered that this spiral nebula existed miles outside of our own Milky Way galaxy – 2.5 million light years to be precise'.

"Without Andromeda as a proxy for spiral galaxies in the universe at large, astronomers would know much less about the structure and evolution of our own Milky Way. That’s because we are embedded inside the Milky Way. This is like trying to understand the layout of New York City by standing in the middle of Central Park," said NASA. what an amazing photograph, for the full article have a look here.