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"
Supernova Remnant N132D in X-Rays
13/09/1999
Thousands of years after a star explodes, an expanding remnant may still glow brightly. Such is the case with N132D, a supernova remnant located in the neighboring Large Magellanic Cloud galaxy. The expanding shell from this explosion now spans 80 light-years and has swept up about 600 Suns worth of mass. The bright regions surrounding the lower right of this X-ray image result from a collision with an even more massive molecular cloud. Towards the upper left, the supernova remnant expands more rapidly into less dense region of space. This image is one of the first ever taken with the High Resolution Camera onboard the orbiting Chandra X-ray Observatory, and records details being analyzed for the first time.