The Crab Nebula, M1, was the first nebulous object
observed by Charles Messier. It is a cloud of expanding gas left
over from a supernova explosion. In the center of this nebula is a
16th magnitude star that is the collapsed core of the supernova. It
is a pulsar, perhaps even a rotating neutron star. M1 can be seen
easily with a pair of binoculars. A telescope will bring out more of
the nebula's fine details.