Portal:Radiation astronomy/X-ray astronomy article/20

SN 185 was a supernova which appeared in the year 185, near the direction of Alpha Centauri, between the constellations Circinus and Centaurus, centered at Right ascension (RA) 14:43:0 Declination (Dec) -62° 30', in Circinus. This "guest star" was observed by Chinese astronomers in the Book of Later Han.

On the right is a "combined image from the Chandra and XMM-Newton X-ray observatories of RCW 86 [in the constellation Circinus showing] the expanding ring of debris that was created after a massive star in the Milky Way collapsed onto itself and exploded. Both the Chandra and XMM images show low energy X-rays in red, medium energies in green and high energies in blue. The Chandra observations focused on the northeast (left-hand) side of RCW 86, and show that X-ray radiation is produced both by high-energy electrons accelerated in a magnetic field (blue) as well as heat from the blast itself (red)."

"Properties of the shell in the Chandra image, along with the remnant's size and a basic understanding of how supernovas expand, were used to help determine the age of RCW 86. The new data revealed that RCW 86 was created by a star that exploded about 2,000 years ago. This age matches observations of a new bright star by Chinese astronomers in 185 A.D. (and possibly Romans as well) and may be the oldest known recordings of a supernova. Supernova explosions in galaxies like ours are rare, and none have been recorded in hundreds of years."