The $1.5 billion Hubble rocketed to space aboard the space shuttle Discovery on April 24, 1990. It’s named after Edwin Hubble, a pioneering American astronomer who furthered our understanding of other galaxies and demonstrated that the universe is continually expanding. About the size of a large school bus, the Hubble orbits at a speed of five miles per second, 353 miles above Earth. At that velocity it can circle the globe in an hour and a half.