When Sputnik began orbiting Earth in 1957, it was a lone satellite. Today, there are thousands of satellites and other remnants of space missions -- so much that the term "space junk" has been coined.

CelesTrak.com categorizes and monitors how many objects -- from communications and weather satellites to the ammonia tank Clayton Anderson pitched from the International Space Station -- are circling the Earth. Its statistics show:

* 5,495 satellites have been launched since Sputnik rocketed into orbit on Oct. 4, 1957. Of those, 3,195 are still in orbit.

* 9,137 pieces of space debris -- rocket bodies, fragments from explosions and the like -- orbit Earth today.

* Russia and the Commonwealth of Independent States has the most satellites of any country in orbit with 3,255. The United States is second with 1,780.

* All told, more than 32,000 objects have orbited Earth since 1957. Of those, 19,688 objects have decayed.