1. Our entire solar system orbits around the center of the about once every 230 million years. 2. The Milky Way and Andromeda galaxies are among a few dozen galaxies that make up our . 3. The Sun appears to rise and set in our sky because Earth once each day. 4. You are one year older each time Earth about the Sun. 5. On average, galaxies are getting farther apart with time, which is why we say our is expanding. 6. Our is moving toward the star Vega at about 70,000 km/hr.