Name of the Object. Messier 1 (M1) or the Crab Nebula Type of Object: Supernova Remnant Equatorial coordinates: J2000.0 : 05h 34m 31,97s; 22° 00\' 52,1\\". Apparente Size: 5\',5 x 5\',0 Constellation: Taurus Description. The Crab Nebula is the remnant of a supernova which was visible from Earth in 1054. This object is expanding continously, which can be seen easily on photographs taken only a few months apart. By measuring this expansion it was inferred that the nebula had been formed some 900 years previously, and that it was the remnant of the famous supernova observed by chinese and by arab astronomers on July 4th 1054. This supernova remnant was first observed by John Bevis in 1731, The well-known astronomer Charles Messier later catalogued it, making it the first member (Messier 1 M1) in his famous catalogue of non-stellar, non-cometary objects. IN 1844 William Parsons made a drawing of M1 in which it appeared to have a shape similar to that of a crab, from which it derived its present name. the nebula is formed from the remains of the material thrown out by the explosion of a supernova, while in the centre there is a neutron star, a pulsar which rotates at some 30 times per second. Pulsars have a density so high that it is equivalent to concentrating the mass of our Sun en a volume of diameter 30 km, or in other terms, a teaspoon of its material would weigh one hundred million tons! Credits: GTC OSIRIS. GTC Team. Daniel López / IAC. Observatorio del Roque de los Muchachos