The idea of the hypernova was first proposed by Dr. Bohdan Paczynski of
Princeton University in
1998. He wanted to explain the
gamma ray bursts that typically last a few
seconds at a time, come from seemingly
random directions in space, and have the potential to produce more energy than anything else in the rest of the
universe for a few seconds. The first remnants of such an explosion were identified by Q. Daniel Wang of
Northwestern University, using work done by Dr. You-Hua Chu of the
University of Illinois at Urbana-Champaigne as a base. The two remnants he identified reside in the galaxy
M101 in the
Ursa Major Constellation. They have been given the easily memorable names
NGC5471B and
MF83. The former is a
nebula that is expanding at at least a hundred miles a second while the latter is one of the largest pieces of
supernova wreckage known at 850
light years across. Both are about ten times brighter than any known supernova remnants in our
galaxy.
Little is known for sure about these powerful explosions, although it is suspected that they are the product of the collapse of extremely massive stars or their collisions with superdense objects such as neutron stars. Both relationships also imply that hypernovae probably have something to do with the formation of black holes. Aside from the physics that I'm not going to butcher by trying to explain, these relationships have been deduced primarily from the locations of gamma ray bursts' points of origin as well as the locations of various remnants of hypernovae, which both tend to be in areas of intensive star formation. Said areas are also hotspots for the formation of neutron stars, black holes, and other associated objects.
Another hypernova that may come to play an important role in our lives in the near future is Eta Carainae. While it is not yet a hypernova, it is suspected that it will probably become one relatively soon due to its unstable patterns of brightness and dimness over the past 150 years that has culminated recently in an intensive brightening spell. It now radiates around 400 million times as much light and energy as the sun and is brightening in a way that astronomers do not understand. On the bright side, though, if it does explode again, it will probably be too far away (7500 light years) to hurt those of us who are protected from gamma ray bursts by an atmosphere. If, however, you are an orbital satellite or have any friends who are orbital satellites, I'd be very frightened indeed.
A really cool picture of Eta Carainae can be found at http://earthfiles.com/earth040.html, where I also got much of the information on it. Most of the rest of the information in this writeup comes from http://www.space.com/scienceastronomy/astronomy/astrobizarre_000928.html.
It should also be noted that I am the layest of lay persons when it comes to this stuff, so if I've gotten anything wrong, please /msg sludgeel so that I can correct it.