The region around the 4.7 magnitude star S Mon is a fascinating mixture of fluorescent hydrogen and dark, obscuring dust lanes. Some dust patches are close enough to bright stars to reflect light from them: these appear blue in colour images 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.