Many people are familiar with the "Pillars of Creation" image. It's been one of the most widely used images from the Hubble of all time.
However, it's now thought that they no longer exist.
The pillars of creation are a small section of a large star forming region in the Eagle Nebula (M16). In such regions, it's not only small stars that are formed, but large stars as well. Large stars are the rock stars of astronomy; They live fast, die young, and go out in a blaze of glory. This blaze of glory is a supernova.
The most massive stars will only live on the order of millions of years, which, astronomically speaking is a very short time indeed. Not long enough for the entire cloud of gas to finish making stars.
Thus, when the most massive stars end their lives, they will tend to take out whatever's nearby. Unfortunately for these pillars, just such a supernova happened right next door. The area cleared out by the supernova looks like it will expand into the pillars in about 1000 years. However, given that it takes light 7,000 years to reach Earth from this region, that means that the pillars were actually destroyed 6,000 years ago.
What we see is only a ghostly image as the final photons of the pillars travels to us.