(M1, Messier 1, NGC 1952, Tauras A, SNR G184.6-05.8)
(supernova remnant in Taurus)
The Crab Nebula (M1, Messier 1, NGC 1952, Tauras A)
is a supernova remnant for a supernova recorded in 1054 (SN 1054).
It is the prototype for an appearance-type of SN remnants termed
a crab-type remnant.
Charles Messier discovered the nebula in 1731, mistaking it
for Halley's Comet until he established that it wasn't moving,
which inspired him to create a catalog of
astronomical objects that could be mistaken for
comets (Messier Catalog).
At about the center of the Crab Nebula is a pulsar
(the Crab Pulsar, PSR B0531+21) with a pulse frequency of
30/second, one of the rare pulsars that have also been identified
optically, and also unique in that its age is known down to the
year.
Crab Nebula characteristics:
The Crab Nebula has been much studied, being
useful in gathering data and testing models.
For example, when pulsars were first discovered,
it was predicted that a pulsar would be found in the Crab Nebula,
and one's subsequent discovery helped confirm the model
that pulsars are spinning neutron stars formed from supernovae.