Our planet and solar system are perched on the edge of an enormous, whirlpool-shaped system of billions of stars. This system, called the Milky Way, is a spiral galaxy that contains hundreds of billions of stars, all rotating around a core about 30,000 light years from our solar system. The bright concentration seen here is the center of that immense whirlpool (actually, the stars are surrounding it, since the center is obscured by huge clouds of gas and dust).
Because the Earth is located inside the Milky Way, it took scientists many years to understand our galaxyΓÇÖs shape and where we fit in it. We now know that the billions of stars of the Milky Way form a pancake-shaped disk with a
