Crab Nebula

The Crab Nebula (also known as Messier Object 1, M1 or NGC 1952) is a gaseous diffuse nebula in the constellation Taurus. It is the remnant of a supernova that was recorded by Chinese and Arab astronomers in 1054 as being visible during daylight for 23 days. Located at a distance of about 6500 ly from Earth, it has a diameter of 6 ly and is expanding at a rate of 1000 km per second. A neutron star in the center of the nebula rotates 30 times per second.

Crab Pulsar

At the center of the nebula is the Crab Pulsar, a neutron star remnant of the supernova which is roughly 10 km in diameter. It was discovered in 1969. The Crab Pulsar rotates once every 33 milliseconds, or 30 times each second, and the beams of radiation it emits interact with the nebular gases to produce complex patterns of wind and fluorescence. The most dynamic feature in the inner part of the nebula is the point where one of the pulsar's polar jets slams into the surrounding material forming a shock front. The shape and position of this feature shifts rapidly, with the equatorial wind appearing as a series of wisp-like features that steepen, brighten, then fade as they move away from the pulsar to well out into the main body of the nebula.

Related Topics:
Crab Pulsar - Neutron star - Remnant of the supernova - 1969 - Pulsar - Fluorescence - Shock front

~ ~ ~ ~ ~ ~ ~ ~ ~ ~