From CFHT Wide Field Imaging Gallery
The composite image is the western region of the molecular cloud B13. Notice the obscuration on the luminous background and the reflections on the sharp edge of the cloud in the lower left of this image from a nearby foreground star (not seen on this image). The reflection on dust is better at shorter wavelengths (for the same matter than dust is more transparent to longer wavelengths) hence this region illuminated by the star appears more bluish than the non-illuminated areas. Notice the increasing reddening of the stars as one gets closer to the cloud: dust mixed with the gas from this molecular cloud absorbs less at the higher wavelengths (I band here) than in the V-band.
Image Title: Molecular Cloud B13 - West Region
Credit: Patrick Boiss (ENS), Jean-Charles Cuillandre (CFHT), Sophie Thoraval (ENS), Laurent Pagani (DEMIRM), Gilles Duvert (LAOG)
Text based on accompanying on-line materials.
Last Modified On: Saturday, December 16, 2000