Chandra Release - December 19, 2023 Visual Description: NGC 2264, Christmas Tree Cluster This release features a composite image of a cluster of young stars looking decidedly like a cosmic Christmas tree! The cluster, known as NGC 2264, is in our Milky Way Galaxy, about 2,500 light-years from Earth. Some of the stars in the cluster are relatively small, and some are relatively large, ranging from one tenth to seven times the mass of our Sun. In this composite image, the cluster's resemblance to a Christmas tree has been enhanced through image rotation and color choices. Optical data is represented by wispy green lines and shapes, which creates the boughs and needles of the tree shape. X-rays detected by Chandra are presented as blue and white lights and resemble glowing dots of light on the tree. Infrared data show foreground and background stars as gleaming specks of white against the blackness of space. The image has been rotated by 160 degrees from the astronomer's standard of North pointing upwards. This puts the peak of the roughly conical tree shape near the top of the image, though it doesn't address the slight bare patch in the tree's branches, at our lower right, which in a living room should probably be turned to the corner! In this release, the festive cluster is presented as both a static image, and as a short animation. In the animation, blue and white X-ray dots from Chandra flicker and twinkle on the tree, like the lights on a Christmas tree.