Pulsars were first noticed by Jocelyn Bell in July 1967.
Most pulsars have a period of rotation between 0.25 seconds
and 2 seconds. Some pulsars however have very different
types of periods e.g PSR 1841-0456 has a period of 11.8
seconds and PSR J1748-2446ad is just 0.00139 seconds.
Pulsar rotation periods are like extremely accurate clocks
with well defined pulse periods.
Pulsars have very gradually lengthening periods as their
rotation slows down over the rest of their life.
The rapid rotation of pulsars is due to the conservation of
the angular momentum of the pregenitor star.|
Likewise the extremely strong magnetic fields can be
attributed to the magnetic flux of the massive star being
compacted and frozen into the small pulsar.
Only by pulsars being neutron stars can we explain how such
a high period of rotation can be maintained without the star
being flung apart.