Apr 1, 2022
A supernova is a massive explosion that occurs at the end of a star's life. The Chandra X-ray Observatory, a sophisticated space telescope, captured the aftermath of such an explosion in the constellation Cassiopeia.
This photo shows the X-ray radiation emitted from the Tycho supernova remnant, first spotted in 1572.
On March 18, 2021, a Japanese amateur astronomer, Yuji Nakamura, spotted a new (new to us Earthlings, anyway) nova in the Cassiopeia constellation, dubbed Nova Cas 2021.
NASA