What Sir John Herschel saw.
Pay close attention to the nearly circular figure in the photo. Hard to imagine, but it is seven light-years wide, and is referred to as a “keyhole” in this image. The moniker came from 19th century astronomer Sir John Herschel, who originally saw a swirling cloud of gass with a hole through it. The interesting name, and beautiful colors that accompany, it have made this the chosen image for the year 2000.