|MadSci Network: Astronomy|
The Sombrero Galaxy (also known as Messier 104 or NGC 4594) is a spiral galaxy about 50 million light years away from us in the direction of Virgo. Determining the number of stars in this galaxy is sort of guess-work. It is an "early-type" spiral, meaning that it has a large central bulge with tightly wound spiral arms. It is currently viewed edge on in such a way that it exhibits a prominent dust ring.
This galaxy is approximately 120,000 light years across (it would take light moving at 300,000 kilometers per second about 120,000 years to cross this galaxy). That makes the Sombrero about as big as the Milky Way galaxy (in which we reside). So as a good first guess, I would estimate it contains as many stars as the Milky Way galaxy, or about 300 billion stars. To give you an idea how big a number this is, if you could count 1 star per second day and night without stopping, it would take you about 9500 years to count all the stars, assuming you could see them all.
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