From the 2Mass Image Gallery
The Trifid Nebula, Messier 20, is only about 1.5 degrees northwest on the sky of the larger Lagoon Nebula, in the constellation Sagittarius. The Trifid, at a distance of about 2 kiloparsecs (or 6520 light years) gets its name from its optical appearance, from three dark dust lanes that divide it. Like the Lagoon, much of the optical emission is dominated by the red light from hydrogen, forming an "H II region" around the bright small cluster of stars in the south. Optically, the remainder of the emission is a blue reflection nebula around the bluer of the two bright stars to the north. In the near infrared we can see through much of the obscuring dust in the Trifid, including the name-giving dust lanes. Many more stars can be seen associated with the nebula in this region near the plane of our Milky Way Galaxy.
This image is a three-band composite constructed from 2MASS Atlas Images. They are infrared images and therefore must be mapped into false colors: J light (1.2 µm) into blue, H light (1.6 µm) in green, and Ks light (2.2 µm) into red. The Atlas Images are produced in the 2MASS Production Processing System. North is up and east is to the left.The text is based on accompanying on-line materials.
Last Modified On: Sunday, December 17, 2000