Hi,
Crankiebabie gave you the words for UFO. Here is one of many, many links:
http://www.qtm.net/~geibdan/framemst.html
It has some explanations about UFO's. You can also do a search online for Roswell, NM. This is the town where many of these Unidentified Flying Objects have been reported. There are also questions about a "secret" Federal Gov't research complex located there, with alleged aliens in it.
Many people have reported seeing lights in the sky at night, very, very fast moving, coming together from 3 other lights into one light, then moving away so fast, it's gone in a heartbeat.