Galaxies Galaxies Stars are not distributed uniformly throughout the Universe.
Stars form within a vast collection of other stars and clusters of stars known as a galaxy .
The Sun is part of a spiral galaxy of about 400 billion stars known as the Milky Way . There are about 100 billion galaxies in the visible Universe. There are about 5000 stars that are visible to the unaided eye. If all those stars were grains of sand, they would fill up the volume of a thimble. If all the 400 billion stars that make up the Milky Way were grains of sand, it would be enough sand for a school yard playground.