On March 26, 1997, police discovered the bodies of 39 members of the Heaven’s gate group who had committed suicide in order to reach what they believed was an alien space craft following the Comet Hale–Bopp, which was at its brightest. Heaven’s gate was an American UFO religion based in San Diego, California.
Such situation should never occur again.
Dec. 21, 2012, won’t be the end of the world (it will just be another winter solstice).
This is the NASA Sciencecast regarding this hoax, myth:
NASA FAQ: http://www.nasa.gov/topics/earth/features/2012.html