The Crab Nebula (M1, NGC 1952, Taurus A) is a supernova remnant in the constellation of Taurus.
The now-current name is due to William Parsons, 3rd Earl of Rosse, who observed the object in 1840 using a 36-inch telescope and produced a drawing that looked somewhat like a crab.
Corresponding to a bright supernova recorded by Chinese astronomers in 1054, the nebula was observed later by English astronomer John Bevis in 1731. The nebula was the first astronomical object identified with a historical supernova explosion.
The Crab Nebula, the result of a supernova noted by Earth-bound chroniclers in 1054 A.D., is filled with mysterious filaments that are are not only tremendously complex, but appear to have less mass than expelled in the original supernova and a higher speed than expected from a free explosion.
The Crab Nebula spans about 10 light-years.
In the nebula’s very center lies a pulsar: a neutron star as massive as the Sun but with only the size of a small town. The Crab Pulsar rotates about 30 times each second.