The reflection nebula M78 in Orion, shown in an R-band CCD image obtained with the UA 16-inch telescope. The field of view shown is 26 arcminutes wide. This cloud lacks the hot stars to ionize its hydrogen, so we see it only as the dust particles scatter light from embedded stars. M78 lies about 2.5 degrees northeast of the trailing star in Orion's belt, ζ Orionis or Alnitak. It would show up somewhat more clearly in a blue-filtered image, since reflection nebulae are bluer than their illuminating stars for the same reason that our daytime sky is bluer than sunlight.
The wider-field view below, from the University of Alabama Crimson Dragon imaging system, shows the environment of M78, from the dark cloud it's part of to a piece of the giant Barnard's Loop nebula (that wraps around half of Orion).
Last changes: 9/2018 © 2006-2018