For six months in 1181, a dying star left a mark in the night sky. The striking object appeared as bright as Saturn in the vicinity of the constellation Cassiopeia, and historical chronicles from ...

In August 1181, astronomers in China and Japan witnessed a bright “guest star” in the night sky that we now know to have been a supernova—one of just a handful of recorded supernovae in our Milky Way ...

This illustration charts the evolution of the SNR 1181 remnant, from its creation when a carbon-oxygen-based white dwarf and oxygen-neon white dwarf merged, to the formation of its two shock regions.

(CNN) — When a supernova was seen glittering in the night sky for six months in 1181, it was so bright that Chinese and Japanese astronomers recorded it as a “guest star” in the Cassiopeia ...

A mysterious remnant from a rare type of supernova recorded in 1181 has been explained for the first time. Two white dwarf stars collided, creating a temporary 'guest star,' now labeled supernova (SN) ...

For six months in 1181, a dying star left a mark in the night sky. The striking object appeared as bright as Saturn in the vicinity of the constellation Cassiopeia, and historical chronicles from ...

Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. For six months in ...

In context: Let's rewind the cosmic clock more than 800 years to 1181 AD. Chinese and Japanese stargazers witnessed a brilliant "guest star" that illuminated the night sky for about six months before ...