NASA has announced that it expects a defunct satellite to tumble to Earth today, but scientists can't say exactly when or where. That's got some people worried. This isn't the first time that space junk has fallen from the sky, though. Gotta Watch brings you some of our favorites.
The clock is tickingÂ – NASA says that a satellite will re-enter the atmosphere sometime today. More than two dozen pieces will remain intact and fall to the ground. CNN's John Zarrella looks at where it might hit.[cnn-videoÂ url="http://cnn.com/video/?/video/us/2011/09/22/zarrella-satellite-falls.cnn"%5D
Free-falling – In September 2004, the Genesis space capsule, which was studying the sun, returned to Earth. The only problem - the parachute didn't open. The crash caused the samples that had been collected to be contaminated. Watch the spectacular plunge.[cnn-videoÂ url="http://cnn.com/video/?/video/us/2011/09/22/von-genesis-crash.nasa"%5D
Like a lead balloon – Balloons can cause major damage when they're the size of a football field. This NASA balloon crashed during takeoff in April 2010, smashing into a car and sending one man running for his life.[cnn-videoÂ url="http://edition.cnn.com/video/?/video/world/2011/09/23/pkg-australia-balloon-crash.abc"%5D