SN 2011dh is a supernova in the relatively nearby Whirlpool Galaxy, M51. The position of the supernova is depicted in the above image. For the third time in the last 17 years a supernova has exploded in the Whirlpool Galaxy. This is unusual for a spiral galaxy which normally only experiences a supernova once or twice a century. Our own Milky Way has not had one observed for about 300 years. In my image, SN 2011dh is much brighter than the foreground stars. This shows the power of the supernova when one considers that the foreground stars are located in our own galaxy and the supernova is over 30 million light years distant. SN 2011dh was discovered by amateur astronomer Amedee Riou in France on May 31, 2011. The NASA APOD image shows M51 before and after the explosion. My image was taken just a few days after the supernova reached its peak brightness of magnitude 12.1. The brightness will decline over the next few months and no longer be detectable in smaller amateur telescopes.
1http://en.wikipedia.org/wiki/SN_2011dh