The universe is full of stars, our sun being only one of literally uncountably many other balls of fire that light up the eternal blackness of space. These stars, however, are not distributed evenly. Instead, almost all of them are grouped together in galaxies. Each galaxy itself is a collection of hundreds of billions of stars, and so far we estimate about a hundred billion galaxies in the universe. At least in the part which we can see.
KeywordsSpiral Galaxy Elliptical Galaxy Interstellar Matter Galaxy Type Lenticular Galaxy
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