On July 4, 1054 AD, observers of the sky were greeted with a new feature when they gazed up at the Taurus constellation.
Noted as a "guest star" by Chinese astronomers, the unfamiliar source of light became 4 times brighter than Venus and was even visible during the day for 23 days.
Unbeknown to astronomers at the time, the unusual bright light was actually caused by a supernova, which today forms what is known as the Crab Nebula.
A supernova is a humongous stellar explosion that most stars are destined for when they reach the end of their life.
Strangely, there is very little documentation of the 1054 AD supernova by European or Arab observers.