Crab Nebula

From Wikipedia, the free encyclopedia

"The Crab Nebula (catalogue designations 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.

At an apparent magnitude of 8.4, comparable to that of Saturn's moon Titan, it is not visible to the naked eye but can be made out using binoculars under favourable conditions. The nebula lies in the Perseus Arm of the Milky Way galaxy, at a distance of about 6,500 ly from Earth. It has a diameter of 11 ly, corresponding to an apparent diameter of some 7 arcminutes, and is expanding at a rate of about 1,500 kilometres per second (930 mi/s), or 0.5% of the speed of light.

At the center of the nebula lies the Crab Pulsar, a neutron star 28–30 kilometres (17–19 mi) across with a spin rate of 30.2 times per second, which emits pulses of radiation from gamma rays to radio waves."

Date :  October 2010
Location : Backridge Observatory, Spruce Knob, West Virginia

Equipment used :
 Lens or telescope -- Homemade 16" Newtonian
 Mount -- AP 1200
 Camera -- SBIG ST-10

Acquistion Software : ACP, MaxIm DL, Focusmax
Processing Software : MaxIm DL, Photoshop

Exposure Detail : LRGB combine    Total hours 3.75