The Crab nebula is the result of a type II supernova explosion observed by Chinese astronomers in 1054. The nebula consists of the outer parts of a red supergiant that exploded after having burned all its fuel. Credit: Hubble Space Telescope
From Live Science:
Telescope images have confirmed something astronomers have long suspected, that red supergiant stars are the stars that explode in so-called type II supernovas.
Type II supernovas are the impressive cosmic explosions that result from the internal collapse of a massive star. (For this reason, they are also known as core-collapse supernovas.)
On average, a supernova will occur about once every 50 years in a galaxy the size of the Milky Way. But scientists don't know when these stellar powder kegs will blow, so identifying the star that birthed them, called the progenitor star, can be tricky.
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