Discovered in 1792 by William Herschel, the Crescent Nebula is the active remains of a dying star. Said star is the bright white one at the center of the nebula. It has gone through its red giant stage and blown off much of it's mass. Even so, it's 600,000 times brighter than the Sun, and 21 times more massive. The ripples in the nebula are caused by the slow moving material colliding with the stronger stellar wind from the newly collapsed star.