Asteroid and Eagle Nebula. Computer illustration of a view across the rocky surface of an asteroid towards a star (bright, centre) and the Eagle Nebula (M16, NGC 6611) in the background. The Eagle Nebula is an emission nebula that lies around 6500 light years from Earth in the constellation Serpens. It is a huge cloud of gas and dust that glows as the hydrogen it contains is ionised by radiation from the hot young stars that have formed within it.