IC 4954 and IC 4955

Click on image for larger version.

These two nebulae, IC 4954 and IC 4955, are part of a much larger complex of newly formed stars. This much larger cluster is called Roslund 4 and astronomers estimate that the stars found here are 4 million years old. The very sharp boundary (shock front) between some of these stars and the molecular cloud serves as a chronometer for the cluster. It is unlikely that a structure like this, caused by the outflow of these energetic young stars, would persist for timescales longer than 6 million years. It is estimated that this star forming region is 6,000-8,000 light years away.


20in RC Optical Systems telescope Operating at f/8.4
SBIG ST10XME CCD camera with color filter wheel

L R G B color production was used to create this image.

Luminance = 150 minutes binned 1x1
Red = 20 minutes binned 2x2
Green = 20 minutes binned 2x2
Blue = 20 minutes binned 2x2

  • While these nebula show some emission, it appears the brightest parts are probably reflection nebulae. Owing to its great distance, this reflection nebula is probably dimmed and reddened to give it this rather strange appearence.
  • Two iterations of L-R deconvolution (sharpening) algorithm using CCDsharp were applied to the luminance image.

  • Minimum credit line: Adam Block/NOAO/AURA/NSF

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    Updated: 06/06/2005