Simeis 147 (also known as Sh2-240) is a supernova remnant some 3000 light years away and is approx 40 000 years old. There is a pulsar, all that is now left of the original exploding star, at the centre.
This image was taken with an Atik 460EX CCD camera through a Canon 200mm lens at f2.8 and with a 3nm Ha filter. It consists of 15 x 1200s subexposures. The image is also shown in reverse to more clearly reveal the structure of this extremely faint nebula. It was taken on the night of 11 Dec 2013.