Link to the star animation

This is an animation of the stars at the central most part of the Milky Way Galaxy.  What's really cool about them, is that they're moving really fast around some central object that can't be seen.  By using the equations derived in the video I made for you today, astronomers have determined that the center of the Milky Way contains a super-massive blackhole, containing 4 million times the mass of our Sun!