On April 16, 2022, Koichi Itagaki, an amateur astronomer in Japan, discovered a Supernova in a galaxy that is 63 million light years away. The galaxy is NGC4647 which is visually very close to Messier object M60, an elliptical galaxy in the constellation Virgo. It was at a magnitude 15 and brightened over the next few weeks to a magnitude 12. When I observed it on May 17th it was a magnitude 13. It was so bright that it was brighter than the galaxy it is in. Its designation is SN (for Supernova), 2022 (for the year), hrs (assigned sequentially, once it is confirmed).
Last year 21,425 supernovae were observed. As of June 3, 2022, year to date, 8,078 supernovae have been observed of which 742 have been confirmed.
Supernovae occur when the star explodes. The star becomes brighter than the galaxy it exists in. SN2022hrs is a Type Ia. Which means it was a white dwarf that experienced a "thermal runaway." These white stars often were a giant red star with a companion star. The giant red star uses up its energy and collapses down to a white dwarf. The white dwarf draws energy or mass from the companion star and the core temperature rises. Eventually the temperature is high enough to ignite carbon fusion. It then undergoes runaway fusion. It will collapse and typically form a neutron star.
Supernovae may be common, but to observe or image one is a real treat for any astronomer.
