Since its discovery at Palomar in 1992, the Guitar Nebula has been observed twice with the Hubble Space Telescope. Read more about the Nebula, and see some pretty pictures, here.
Results from comparing the HST observations in December 1994 and December 2001 are shown below. Both images are at a wavelength of 656 nm, and have been enhanced ("prettified") by suppressing the noise. (All pixels within 2 sigma of the mean have been replaced by the sky background.)
Read more about the Nebula here, or look at the sequence of images from Palomar Observatory.
Last modified: 18 Feb 2002