Satellite Quiz: How Well Do You Know What's Orbiting Earth?
by SPACE.com Staff | July 10, 2012 07:00am ET
The space age dawned with the launch of Sputnik 1, Earth's first artificial satellite, in 1957. Thousands of additional spacecraft have followed in Sputnik's footsteps, serving humanity in a variety of ways. How well do you know Earth's satellites?