A white dwarf star in galaxy M82 has exploded. Fed on a diet of hydrogen and helium from a neighbour that was a bit too close, it suffered a terminal case of cosmic indigestion. That little snack pushed it over the Chandrasekhar mass limit (1.4 solar masses) and induced a runaway nuclear reaction – the entire star is blown apart.(Type 1a SN).
Because all type 1a supernovae are of similar mass and composition, when they explode,they are equally luminous and thus act as “standard candles” for astronomers to confirm distances.
M82 lies close to Ursa Major and the Supernova is quite easily seen close to the galactic core. It should get considerably brighter over the next few days and may get to binocular brightness.
I set up my Nexstar 8SE and aligned with a 36mm Baader Hyperion eyepiece. With M82 in view, I swopped to a 22mm Nagler T4. M82 was easily visible – there was 1 bright field star and just beside it was the supernova which looked like another bright star. I tried a 17.3mm Delos but thought the Nagler view was better.