This is the nebula rich region in the constellation of Monoceros the Unicorn with the dark Cone Nebula (left of centre) and the small V-shaped and bright Hubble's Variable Nebula at bottom, a reflection nebula that varies in form and brightness. Above the Cone Nebula is the triangular Christmas Tree Cluster, NGC 2264, here upside down as the bright blue star 15 Mon is the base of the tree. The large region of nebulosity is Sharpless 2-273. The V-shaped dark nebula above centre is LDN 1603.

15 mon christmas tree cluster cone nebula eos ra h alpha hnt150 hubbles variable nebula l enhance ldn 1603 monoceros ngc 2251 ngc 2261 ngc 2264 optolong reflection nebula sharpstar sharpless 2 273 trumpler 5 astrograph emission filter star cluster sky astronomy astro photography skies science nature astro