The Cone Nebula and the Christmas Tree Cluster, NGC 2264, are about 2,700 light-years away in the constellation Monoceros (just to the east of the constellation Orion). The cone-shaped Cone Nebula is on the far left. Most of the field glows with the red light emitted by hydrogen gas. The blue section near the center shines with starlight that is tinted blue as it filters through fine dust particles. The portion of the nebula to the lower right of the bluish section is known as the Fox Fur Nebula. The detail below shows why the star cluster is named the Christmas Tree Cluster.
128 minutes Ha on 2014-02-28 using an Astrodon 3 nm H-a filter, 88 minutes L on 2013-03-09, 104 minutes L on 2014-02-26, 120 minutes RGB on 2013-03-09, and 96 minutes RGB on 2014-02-28, all using a QSI 583 from northern New Jersey through an Astro-Physics 105mm refractor at f6.2. North is to the right in the image above and down in the image below. ©2014
This orientation makes it clear why the star cluster is named the Christmas Tree Cluster.