On this day in 1054: How China Discovered the Crab Nebula- The Song’s Era of Science

The Crab Nebula is undoubtedly one of the visual wonders of the known universe. Created from a spectacular arrangement of ionized helium and dust, the Nebula represents the remnants of a supernova star which at some point in the distant past exploded. Formally identified in 1731, the arrangement is visible from Earth via the use of binoculars or a telescope.

However, few know the full story as to how this interstellar icon was first in fact discovered by China, over 600 years before the revival of Western Astronomy in the European Renaissance. The destruction and implosion of the supernova which created the nebula was in fact observed by Chinese astronomers, who in 1054 described the phenomenon as a “guest star” (客星), who observed the appearance of a bright star in the sky that was previously not present.

China in the 11th century was ruled by the Song Dynasty, which whilst it competed with rival kingdoms including the Liao and the Western Xia, and later the Jin, was nonetheless one of the most technologically advanced countries in the world. It would meet its end against the Mongol Empire but this does not negate its extraordinary achievements in innovation.

The Song oversaw the invention of the compass, printed paper money, gunpowder and hydraulic engineering whilst making incredible advances in botany, zoology, geology, mineralogy, mechanics, magnetics, meteorology, horology, pharmaceutical medicine, archaeology, mathematics, cartography, optics and art, all of which would shape the course of the nation’s history into the long term future.

Astronomy was but one amongst many of these achievements. During the era by which the Crab Nebula was discovered in its preliminary supernova explosion, the Song heralded a famous scientist and statesman known as Shen Kuo, who would work with another astronomer called Wei Pu. Shen led the dynasty’s bureau of astronomy and discovered the magnetic concept of the “true north”- and with Wei aimed to focus on the orbital speeds and and positions of the planets.

On this background, it is hardly surprising that astronomers in China made breakthroughs on matters of celestial bodies which pre-dated the achievements of European countries by centuries. As China mapped the stars, the Kingdom of England had not even undergone the Battle of Hastings and the basic record keeping of the Domesday Book. As Shen and Wei sought to map out the Cosmos, the west would believe the universe revolved around the Earth for another 600 years.