China was able to contribute to the developments in the science of astronomy critically. In their philosophy, the harmony between earth, the sky and humankind were essential, and therefore any disturbance to that balance had to be predicted. This believe caused the astronomers of the historical China a great status, they were able to predict comets like no other culture. Also, the precise predictions were caused by the critical consequences the responsible astronomer had to face in case of a false prognosis.
In 1054, the Chinese astronomers of the Song dynasty documented seeing a bright star on the celestial sphere, it was visible in daylight for more than three weeks, they classified it to be a ‘guest star’ and it took about nine centuries to prove them wrong. In 1731, John Bevis (and later Charles Messier) discovered at the same location, where the Chinese astronomers first saw the ‘new star’ a nebula. Through the years many documents of the observation concerning this bright happening in the sky were collected and finally, in the early 20th century, when it became possible to photograph the nebula, researchers found out that it originated from a supernova. A supernova is defined as a sudden stellar explosion, which is, depending on the masses of the star, tremendously bright. The supernova of the year 1054 had a luminosity of -6 apparent magnitude and counts as one of the brightest supernovae in history (at least from what humankind could measure). Only the supernova of 1006, which happened in the constellation of Lupus was brighter with a luminosity of -7.5m (just for comparison, Venus as the brightest of all planets has a maximum luminosity of -4.89 and the full moon is -12.7).
In the 18th century, Charles Messier was going to observe a comet and confused it with the Crab nebula that resulted from the supernova of 1054. In 1758 he created the Messier Catalogue of astronomical objects with the Crab nebula as its first entry, M1. It was made for the purpose of distinguishing non-cometary nebulae from comets. At the center of the Crab nebula lies the Crab Pulsar, a neutron star (or spinning ball of neutrons), 28–30 km across, which emits pulses of radiation from gamma rays to radio waves with a spin rate of 30.2 times per second.
At yovisto, you might learn more about supernovae watching the lecture Exploding Stars – Celestial Fireworks by Prof. Dr. Alex Filippenko from UC Berkeley or the lecture Supernovae by Charles Bailyn from Yale University.
- The Cosmos
Professor Jay M. Pasachoff
Cambridge University Press, 2013
- The Cosmos. Astronomy in the New Millennium
Professor Jay M. Pasachoff
Thomson Learning, 2003