One of the most famous is the Supernova of 1054, which created the Crab Nebula.

On July 4, 1054, Chinese astronomers observed what they called a "guest star." This was one of 75 "guest stars," (novae or supernovae -- not comets, which have a different name) recorded between 532 BCE and 1064 CE. This star was four times brighter than Venus and was visible even in daylight for three weeks.

It was such a remarkable appearance that the Anasazi of North America created a set of petroglyphs describing the star and its approach to the crescent moon. It also appears briefly in an Italian record reprinted in the 15th century.