Crab Nebula
Crab Nebula is a supernova remnant in the direction of the Taurus and a Pearl Sewn Nebula. In 1731, John Bevis discovered. It is a celestial body formed by explosion of 1054 supernova, which appeared in 1054 and recorded in the Arab Empire, China, and Japan. Crab Nebula is the strongest and most sustainable source of energy in the sky and its size exceeds 1012 eV, among which X-ray and gamma-ray energy is more than 30 keV. It is about 6,500 light years away from Earth, and the diameter of the nebula is 11 light years. It is now spreading from the center to the outside at a speed of 1,500 km / sec. It is also part of the Perseus arm of our galaxy. At the center of the nebula, there is a Crab Nebula pulser with a diameter of 28 to 30 km, which emits electromagnetic waves while rotating 30.2 times per second. It is the first celestial body associated with a supernova explosion in human history. When occlusion occurs, researchers use electromagnetic waves and nebulae to cover the nebula.