This supernova was observed by Chinese astronomers in 185 CE. The Chinese kept meticulous astronomical records for centuries, including observations of what modern scientists interpret as supernovae. Chinese astronomical records from 185 AD describe the appearance of a “guest star” in the constellation now known as Circinus. This guest star matches the expected location and timing for a supernova that would leave behind RCW 86.
In the shadowed forests of the Late Carboniferous, long before mammals, birds, or even dinosaurs,
