Exploring the Crab Nebula

A supernova is an exploding star whose luminosity -- after exploding -- suddenly increases millions of timesl. A supernova remnant, therefore, is the cloud gas resulting from the explosion.
The Crab Nebula is located 6300 light years away, in the constellation of Taurus. Though not visible to the naked eye, it could be seen using binoculars in favourable conditions.
Chinese astronomers first noticed the star's demise in 1054 AD. During the explosion, it was six times brighter than our sun and was visible even in daylight for at least a month during the time, and for a year during nighttime.
Because the energy emitting from a supernova is extreme, the mass is casted out at hundreds of kilometres per second.  And because the mass acts as a kind of vacuum, it appears asymmetrical, with different shapes and forms. A Lord Rosse found this supernova remnant's structure similar to that of a crab.
About 600 years after the Chinese noticed it, the doctor and astronomer John Beavis re-discovered it and added it to his cloud atlas in 1731.
Later, the French astronomer Charles Messier included it as the first entry in his “Catalogue of Nebulae and Star Clusters”, which was published in 1774.
It was a fascinating subject for astronomers for years and was studied in depth for many years.
In 1948, the German astronomer Walter Baade noticed that the Crab nebula was emitting some very strong radio waves.

A pulsating radio source was discovered by astronomers in Puerto Rico, later identified to be a rotating neutron star, spinning 30 times per second. A neutron star is a celestial object with a very small radius and very high density composed primarily of closely-packed neutrons. This produces a gravitational field 300,000 times of that of Earth. It acts like a giant electric power generator, producing 100,000 the times of power our sun produces.
The Crab Nebula's pulses will become less strong as time passes and its X-ray emissions will disappear. It will gradually disappear in a few thousand years.
The Crab Nebula has been the popularised by many writers, particularly during the '40s and '50s, considered the golden age of science-fiction. Authors such as Murray Leinster, Malcolm Hulke, Dennis Felltham Jones, among others, have written on it.
Even our own popular sci-fi writer Dr. Muhammad Zafar Iqbal has penned a book on the subject.

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