NASA TV UFOs: NASA Camera Films
UFO Descending towards the Earth

NASAs camera apparently follows an unknown, pulsating object, which descends towards the Earth, before NASA loses interest and turns the camera around.

The UFO is seen in the lower right corner of the screen, and enters the screen 20 seconds into the video:

http://www.youtube.com/watch?v=b7DGI7OhN-4