Although the irregular galaxy M 82 is approximately 12 million light years from the Milky Way, it is considered a close neighbor. On the 21st of January that neighbor became the talk of the neighborhood when it was found sporting a brand new supernova. Of course, in Astronomy, brand new is a relative term. It is a sobering thought to realize this several week long pulse of light has been traveling for 12 million years and will pass us by and continue on out into the universe.
It was first noticed by students using one of the 0.35 meter reflectors at London University’s observatory. Threatening weather forced a cancellation of the regularly scheduled instruction for a quick demonstration of CCD usage. The students choose M 82 as the target. A check of the image showed a star that the instructor did not remember from earlier observations. A quick search of archival images verified the interloper as transient, and the rest is history.
As the announcement of a potential supernova (PSN J09554214+6940260) spread, many telescopes turned their attention to M 82. Spectroscopic images showed it to be a type 1A supernova a couple of weeks shy of maximum brightness.
My ‘after’ image was taken on the evening of the 22nd of January. It measures a magnitude 11.2 but that is too bright as I cannot measure the star without including light from the galaxy. Measurements taken on the 31st show a magnitude of 10.5, but modeling shows that it will peak during the first couple of days in February, so it won’t get much brighter.
By pure chance I took the ‘before’ image on the 3rd of January. Since the image on the 3rd was taken for 30 seconds through a luminance filter, I used the same settings on the 22nd in an attempt to match the two for the animation. I am surprised how close the images match.