Crab nebula

The Crab Nebula (catalogue designations M1, NGC 1952, Taurus A) is a supernova remnant and pulsar wind nebula in the constellation of Taurus. The nebula was observed by John Bevis in 1731; it corresponds to a bright supernova recorded by Arab, Chinese and Japanese astronomers in 1054. At X-ray and gamma-ray energies above 30 keV, the Crab is generally the strongest persistent source in the sky, with measured flux extending to above 10¹² eV. Located at a distance of about 6,500 light-years (2 kpc) from Earth, the nebula has a diameter of 11 ly (3.4 pc) and expands at a rate of about 1,500 kilometers per second. It is part of the Perseus Arm of the Milky Way Galaxy.

A supernova (abbreviated SN, plural SNe after supernovae) is a stellar explosion that is more energetic than a nova. It is pronounced  /ˌsuːpərˈnoʊvə/ with the plural supernovae /ˌsuːpərˈnoʊviː/ or supernovas. Supernovae are extremely luminous and cause a burst of radiation that often briefly outshines an entire galaxy, before fading from view over several weeks or months. During this short interval a supernova can radiate as much energy as the Sun is expected to emit over its entire life span. The explosion expels much or all of a star's material at a velocity of up to 30,000 km/s (10% of the speed of light), driving a shock wave into the surrounding interstellar medium. This shock wave sweeps up an expanding shell of gas and dust called a supernova remnant.