Supernova in NGC 6946 in Cepheus

A aupernova occurs when a star whose mass is orders of magnitude greater than the sun becomes unstable and ends its life in a spectacular fashion -- by blowing up. This is a relatively rare event, but in a galaxy with millions and millions of stars, one becomes visible every few years or so: if you happen to be looking in the right place at the right time. Seven previous supernova have been detected in 6946, the first in 1917 and the last in 2002.The supernova area, enlarged from the image at left.  The other three stars in the field are foreground stars in our own galaxy. An enlagement of the Digital Sky Survey image; the supernov is not present here.  "Blink" animation showing the supernova; the image area is outlined in the box on the image at left. The image used for the pre-supernova image is from the Digital Sky Survey from a few years ago.            


     
Camera  |  Chip Temperature SBIG ST-2000XM   |   -15C
Exposure Data Luminescence: 60 minutes binned 2 x2
Telescope |  Focal Ratio / length (mm) 12" (30cm) SCT  |   (reduced to) F 6.3 / 1890mm
Mount  | Guiding Meade LX200 classic | TC-211 guider chip camera CCDOps self-guide at 3 secs /f rame
Reduction Darks only; 10 frames average combined master dark
Object Information 8.9 magnitude,11 arc minute diameter face on spiral galaxy in Cepheus, aproximately 10 million light years distant. Coordinates: RA  20:34  Dec + 60:09
Image notes North is to the left; the image was rotated to bring the supernova area to top.  No flat was used, so the image is cropped to a roughly 14 x 14 arc minute field of view.  Combined in CCDSoft v5; curves, levels, and cropping in Photoshop 7.