The Dumbbell Nebula, M27, is a classical example of a planetary nebula. As such, it is the remains of an old red giant star whose outer layers were ejected into space. This gas is ionised and energised by strong ultra-violet emissions from the exposed hot core of the original star. This phase of the star’s life is rather short, at only a few tens of thousands of years, before the ultra-violet emission declines and the ejected gas becomes invisible. There is a star visible at the centre of this structure, which may be the original star. It is about 1200 light-years away and has been expanding for something like 10,000 years. It is just over 1 light year in diameter so it is fairly large in the sky, and is an easy object for telescopes and even binoculars.