A star is a huge nuclear reactor, fusing light elements into heavier elements. Each element builds up a shell, from a light hydrogen skin to a dense core. For stars big enough to build a massive iron core, the star eventually explodes in a supernova, like Cassiopeia A.
NASA has created the first ever map of radioactive material in a supernova remnant, revealing one of the biggest mysteries in the universe: How stars blow up in these explosions, sowing the universe with heavy elements like iron, titanium or gold.
Check out the amazing new image that NASA just released of Cassiopeia A, the remains of a supernova that would have been visible from Earth 300 years ago. This new composite image was released to promote a new 3-D visualization tool that will allow more people to study Cas A.
In 1660, Britain restored the monarchy after a decade of Oliver Cromwell's puritanical dictatorship. Charles II's supporters pointed out that his birth was marked by a glorious noon-day star, proving his divine right to rule...and that wasn't necessarily just propaganda.
It takes a lot of imaging power to capture the awesome aftermath of a star committing suicide. To get this freaktastic death blossom pic of supernova remnant Cassiopeia A, it took three of NASA's Great Observatories, using three different light wavebands. The red is from the Spitzer Space Telescope's infrared data,…
You can still see the shock wave from the explosion of supernova Cassiopeia A in this color-enhanced image from NASA's Spitzer Space Telescope. The blue glow around the dead star is the "forward shock," material blasted with energy by the shock wave when the star blew. Click through for a gallery of the biggest space…