AAO image reference AAT 14a. « Previous || Next »
Top left is NE. Image width is about 42 arc min
Image and text © 1999-2010, Australian Astronomical Observatory, photograph by David Malin.
The region around the 4.7 magnitude star S Mon is a fascinating mixture of red fluorescent hydrogen and dark, obscuring dust lanes. Some dust patches are close enough to bright stars to reflect light from them; these appear blue for the same reason that the day-time sky is blue - because some of the interstellar particles preferentially scatter blue light. Some of the wispy tendrils of nebulosity are Herbig-Haro objects, jets of matter ejected from newly-formed stars still hidden within the nebula. About 250 stars have been recognised as members of NGC 2264 which is in Monoceros at a distance of about 2700 light years.
Related Images
AAT 13. The Cone nebula in the NGC 2264 cluster
AAT 14. NGC 2264 and S Monocerotis
AAT 14b. The Fox-fur nebula
UKS 29. The Cone nebula and Trumpler 5
Constellation of Monoceros (external site)
For details of photographic exposure, search technical table by AAT reference number.