RCW 61

This image, RCW 61, also designated as Gum 41, is part of the Running Chicken nebula (IC 2944). Some say RCW 61 is the head of the chicken, some say the feet and some say it's the wing, personally I have never been able to see a chicken - until now - see the second image that I found on the internet!
The Nebula is formed by a binary star system, two rare O-type stars in very close orbit around each other, this double star is known as HD 100099. O-type stars are extremely luminous and massive blue stars.The massive amounts of energy emitted by the central binary star system is what has caused the ionisation of the surrounding gas as well as hollowing out a cavity around themselves. The circular shape of the nebula also shows the boundary of how far the energy coming of those two stars can reach.
O-type stars are also quite volatile and short lived. They tend to end their lives in a supernova or collapsing into a black hole. RCW 61 sits around 7,500 light years from earth.