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My previous post was about a star that is shedding pieces of itself out into space. The above picture is of another star, but in this case the star literally blew itself apart. What you see is the remnants of a supernova. Very large stars do this at the time when they start to run out of fuel when gravity takes over imploding the leftover material, then exploding soon after.
Astronomers have determined that the star exploded in 1054 A.D. and was recorded by Chinese and Arab astronomers. The star they saw was so bright, it was visible in the daytime sky. Almost 700 years later, John Bevis was the first person to observe the expanding remnants through a telescope. It was rediscovered in 1758 by Charles Messier, a comet hunter, where he placed it as the number 1 non-comet object in his catalog. The Earle of Rosse observed it in 1840, made a drawing of it in the shape of a crab, therefore also known as the Crab Nebula.
Part of the star that exploded is still at the center of the nebula. It is now a pulsar, which is a spinning neutron star, only 12 miles across. It spins at 30.2 times a second and emits pulses of radiation. Photographs taken over the years showed that it is expanding over 900 miles per second. It is now 11 light years across and is located about 6500 light years from us.
Technical Data is the same as the previous post.