Christmas Tree Cluster: NGC 2264 glows a festive red
A glowing nebula and bright blue star cluster combine to produce a festive deep-sky object known as the Christmas Tree Cluster.
This is NGC 2264, an object that consists of both the Cone Nebula and accompanying Christmas Tree Cluster.
The source of the latter nickname is obvious: it would be difficult to find a more festive-looking deep-sky object, with its glowing red Christmas tree-shaped nebulaic cloud and a star cluster of cosmic baubles.
Deep within the clouds of gas and dust are the ingredients for producing new stars, which burn a fiercely hot bright blue. The red hue in the image is a result of gas clouds glowing as they are hit by ultra-violet light emanating from the newborn stars.
The region is about 30 lightyears across, and is located in the Monoceros constellation about 2,600 lightyears from Earth, not far in the sky from the Orion constellation.
Astronomer William Herschel discovered the cluster itself in January 1784, and then went on to locate a section of the glowing cloud about two years later at Christmas time.
The bright star at the top of the 'tree' is a massive multiple star system that emerged from within the gas and dust a few million years ago, while the dark patch at the bottom of the image is the Cone Nebula itself.
This image was captured using the Wide Field Imager camera attached to the 2.2-metre Max-Planck Society/ESO telescope at La Silla Observatory, 2,400m high in the Chilean Atacama Desert.
It took 10 hours to capture all the date required to produce the full picture of the Christmas Tree Cluster.
Observatory La Silla
Release date 16 December 2008
Iain Todd is BBC Sky at Night Magazine's Staff Writer. He fell in love with the night sky when he caught his first glimpse of Orion, aged 10.