The Crab Nebula
The Crab Nebula is a supernova remnant.
Embedded within it is a radio pulsar.
The supernova was observed
in 1054 A.D.
The supernova event was visible to the naked eye in the daytime; it
was as bright as Venus.
The filaments in the nebula are seen to be expanding at 1000 km/sec.
The total mass of ejected material is about 0.1 solar masses.
The distance to the Crab Nebula is about 6500 light years.
The diameter of the remnant is 6 light years.
A pulsar was discovered in the center of the nebula in 1969.
The neutron star in the center of the Crab rotates 33 times per second.