As reported in a single Chinese record, the supernova of 185 AD was visible for at least 8 months and reached a brightness comparable to Mars. In 2007, optical, radio, and X-ray emission observed at a location consistent with the Chinese record make RCW 86 the prime candidate for the remnant of SN 185 AD. Combined images from the Chandra (upper left and lower right boxes) and XMM-Newton X-ray observatories show low, medium and high-energy X-rays in red, green, and blue respectively. By studying the distribution of X-rays with energy, and measuring the remnant’s size, scientists now surmise that RCW 86 was created by the explosion of a massive star roughly 2,000 years ago.
Image credit: Chandra: NASA/CXC/Univ. of Utrecht/J.Vink et al.; XMM-Newton: ESA/Univ. of Utrecht/J.Vink et al. Larger image
