A supernova is a violent stellar explosion that can shine as brightly as an entire galaxy of billions of normal stars. Astronomers divide supernovae into two primary groups: Type Ia and Type II. Type Ia supernovae form as a white dwarf "steals" hot gas from a companion star. If enough gas piles up on the surface of the white dwarf, a runaway thermonuclear explosion blasts the star to bits, leaving nothing behind. These are the brightest supernovae, and can be used to measure the distances to other galaxies. A Type II supernova is the final stage in the evolution of a star that is at least eight times as massive as the Sun. Such a star reaches a point where it can no longer produce nuclear energy in its core. Without the outward pressure created by this energy, gravity wins out and causes the star's core to collapse to form a neutron star or black hole. The star's outer layers "rebound" violently, blasting into space at several percent of the speed of light.

Radio Programs

Aludra The showiest “dog” star of all Wednesday, January 13, 2016
The Dog’s Tail The big dog wags its tail — after this. Tuesday, January 12, 2016
Crab Nebula A crab scuttles across the sky Monday, December 14, 2015
Runaway Star A stellar “runaway” in the charioteer Saturday, November 14, 2015
Eta Carinae Impressive stellar siblings Tuesday, October 20, 2015
More Andromeda Galaxy Getting ready to put on a show Thursday, September 17, 2015
Making a Magnetar Making a powerful magnet Thursday, August 6, 2015
Doomed Stars Two stars with a bright future Wednesday, June 17, 2015
Small but Bright Tiny stars put on brilliant displays Tuesday, June 16, 2015
Two Ways to Die Two ways to make a supernova Monday, June 15, 2015
MY Camelopardalis A brilliant duet for the giraffe Sunday, March 15, 2015
Bright Paw The big dog’s brilliant paw Friday, February 13, 2015
Morning Moon A bright future for the scorpion Thursday, February 12, 2015
Iron Ironing out a heavy element Thursday, February 5, 2015
Brightest The brightest outbursts in the universe Thursday, November 6, 2014
Even Brighter A couple of brilliant ways to die Wednesday, November 5, 2014
Doomed Giant A big star with a brilliant future Wednesday, September 24, 2014
Eagle Nebula Inspirational beauty in the southern sky Saturday, June 21, 2014
Moon and Antares The amazing fate of a giant star Wednesday, June 11, 2014
Moon and Spica Violent scenarios for a binary star Sunday, May 11, 2014
Time Bombs Time bombs in the evening sky Wednesday, April 23, 2014
Moon and the Scorpion Doomed stars in the scorpion Thursday, April 17, 2014
Supernova Factory A galaxy with a steady supply of fireworks Tuesday, March 25, 2014
Pulsar Tales Dead stars that won’t shut up Tuesday, August 20, 2013
Moon and Antares Clouding up nearby space Thursday, July 18, 2013
Giant Blast Blasting apart a giant star Wednesday, July 3, 2013
‘Medium’ Nova A mid-size stellar explosion Tuesday, July 2, 2013
Vela A giant cloud of stellar debris Thursday, April 4, 2013
Neutron Stars Gravity wins the stellar battle Thursday, March 21, 2013
Stellar Tease The third time’s the charm Wednesday, March 20, 2013
Guitar Nebula Strumming a few astronomical notes Saturday, March 16, 2013
Pulsar Planets Reborn from a violent demise Tuesday, March 12, 2013
Moon and Antares Two stars with different fates Sunday, March 3, 2013
Flashy Neighbor Evidence of a flashy neighbor Tuesday, January 22, 2013
Multiple Blasts Multiple explosions from a single star Friday, November 2, 2012
More Moon and Antares A stellar recycling project Friday, September 21, 2012
Stellar Suicide A double suicide among the stars Monday, April 9, 2012
Supernova 1987A, III A picture-perfect stellar explosion Thursday, February 23, 2012
Supernova 1987A, II Hunting for an elusive neutron star Wednesday, February 22, 2012
Supernova 1987A Blasting a giant star to bits Tuesday, February 21, 2012

Featured Images

Hubble view of the Crab Nebula
Spectacular Crab Monday, December 14, 2015
Artist's concept of MY Camelopardalis, a contact binary star system
Close Twins Sunday, March 15, 2015
Artist's concept of Supernova 1987A
Time Bomb Wednesday, April 23, 2014
Hot Dust Tuesday, January 7, 2014
The Pencil Nebula, a portion of the giant Vela Supernova Remnant
Blast from the Past Thursday, April 4, 2013
A supernova remnant in the Large Magellanic Cloud
Double Suicide? Monday, April 9, 2012
Hubble Space Telescope images of the aftermath of Supernova 1987A
Wave of Destruction Thursday, February 23, 2012
Hubble Space Telescope image of the aftermath of Supernova 1987A
Stellar Ghost Tuesday, February 21, 2012


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