Supernova
A supernova is the explosive death of a star, during which it rapidly ejects most of its mass in a brilliant burst of light. In core‑collapse supernovae (Types Ib, Ic, II), massive stars (≥ 8 solar masses) exhaust their nuclear fuel, collapse under gravity, and explode. In Type Ia supernovae, a white dwarf in a binary system undergoes runaway fusion after accreting mass. These events deliver heavy elements into space, leave behind neutron stars or black holes, and power typical shock‑front supernova remnants.
Source: heasarc.gsfc.nasa.gov
APODs including "Supernova"
Colliding Supernova Remnants
02/10/1997
When a massive star exhausts its nuclear fuel it explodes. This stellar detonation, a supernova, propels vast amounts of starstuff outwards, initially at millions of miles per hour. For another 100,000 years or so the expanding supernova remnant gradually slows as it sweeps up material and ultimately merges with the gas and dust of interstellar space. Short lived by cosmic standards, these stellar debris clouds are relatively rare and valuable objects for astronomers exploring the life cycles of stars. Yet this double bubble-shaped nebula 160,000 light-years away in the Large Magellanic Cloud may represent something rarer still - the collision of two supernova remnants. This image in the light of excited Hydrogen atoms along with images at X-Ray, radio and other optical wavelengths, suggests that the bubbles are indeed two separate regions of hot gas surrounded by cooler dense shells begining to interact as they expand and make contact.