A Long Time Ago, In a Galaxy Far, Far Away

53 million years ago a massive star in the galaxy NGC 4088 lost its battle with gravity and collapsed upon itself. The resulting collapse increases the temperature and pressure near the center of the star until a massive rebound, or explosion, occurs. This explosion which destroys most of the star is visible to us as a supernova. Though the supernova occurred 53 million years ago, it took the light from that explosion 53 million years to reach Earth which is why we are only seeing it now.

The supernova has been designated SN2009dd and was discovered by 2 independent teams of Italian astronomers. On the night of 2009 April 13, Giancarlo Cortini (Preparrio, Italy), Alessandro Dimai (Cortina d’Ampezzo, Italy) and Elisa Londero (Gemona, Italy) found imaged the supernova. Cortini was the 1st to notice the “super new star”. After a preliminary note was posted, Dimai and Londero found the object in images they took as part of their CROSS survey for new supernovae.

BVR image of SN2009dd in the galaxy NGC 4088. Images taken by Carl Hergenrother with the U of Arizona Kuiper 1.54-m telescope on 2009 May 28.

The above image is a composite of images taken in B (blue), V (yellow) and R (red) filters with the University of Arizona’s Kuiper 1.54-meter telescope on Mount Bigelow. I don’t usually observe supernova (mainly comets and asteroids) but I was helping a friend who was planning a program to observe supernova. Since SN2009dd was the most picturesque one currently observable, it made a great target. The supernova is the star very close to the center of the galaxy. The 2 yellow arrows point at the location of the supernova.

The galaxy (NGC 4088) the supernova is located in is located in the constellation of Ursa Major, the same constellation that contains the Big Dipper. The galaxy is magnitude ~11.2 which makes it a tough target for telescope users unless you have either a large scope or live at a very dark location. The supernova itself peaked at magnitude 13.5 in early April. By the time of my observations on May 28, it had only dimmed slightly to about magnitude ~13.8.