The Eagle Nebula (M16) lies in the small constellation Serpens Cauda, just north of Sagittarius. It is a little more than 2 kpc from Earth and at apparent magnitude 6 it can be identified easily with binoculars (see this animation). This nebula became famous when the Hubble Space Telescope images were released in 1995 indicating that stars were forming in great pillars of gas and dust. We shall discuss this star formation in M16 in Chapter 20.
Since the stars in the Eagle Nebula are still being formed, it can be viewed as a very young open star cluster. The nominal age is only several million years.