About half of the stars we see are double stars. Double stars are to stars held in gravitation, and revolve around a common center together. They can also be called binary stars. When looking at the sky on a clear night from either the Northern or Southern hemisphere you can see about 4,500 stars. Binoculars bring about 1,000 into view. The milky way, which is our galaxy has more than 1,000,000,000 (one billion) stars. Because the Milky Way is only one of billions of galaxies, their must be trillions and trillions of stars. Probably more than a person could count in an entire lifetime. The nearest star to our sun is Alpha Centauri A. It is 4.3 light years away. It is slightly bigger and brighter than the sun. Space between stars is not completely empty. In some places there are great clouds of gas and dust. They can be many light years across.