Astronomers have released a new image of the supernova remnant Pa 30, the expanding cloud of gas and dust left behind by a stellar explosion observed from Earth in 1181. The remnant, located about 6,500 light-years from Earth in the constellation Cassiopeia, is expanding at a rate of roughly 600 kilometers per second, according to measurements from the International Gemini Observatory.

The explosion was a type of supernova known as a Type Ia, which occurs when a white dwarf star accumulates enough mass to trigger a thermonuclear detonation. Unlike most supernovae, this event was not detected at the time it happened; historical records from Chinese and Japanese astronomers describe a bright, slowly fading star in the same region of the sky, which modern analysis has linked to the remnant.

The new image, assembled from data collected by the Gemini North telescope in Hawaii and processed by researchers including T. Cunningham of the Center for Astrophysics and Smithsonian Astrophysical Observatory, reveals intricate filaments of ionized gas glowing in shades of orange and red. The remnant’s structure provides insight into how such explosions disperse heavy elements into space, contributing to the chemical enrichment of the galaxy.

NASA and the National Science Foundation, which jointly support the Gemini Observatory, emphasized that the observation was part of ongoing efforts to understand the life cycles of stars and the mechanisms behind cosmic explosions. The image was released as part of the Astronomy Picture of the Day series, a long-running public outreach initiative that features daily visual explanations of astronomical phenomena.