Image composite compares infrared and visible views of the famous Orion nebula and its surrounding cloud, an industrious star-making region. The infrared picture is from NASA's SST, and the visible image is from the National Optical Astronomy Observatory. The Orion nebula is the largest and takes up the lower half of the images; the small nebula to the upper left of Orion is called De Mairan's Nebula and the medium-sized nebula at the top is the Running Man Nebula. Each nebula is marked by a ring of dust that stands out in the infrared view. The visible view of the nebulas shows gas heated by ultraviolet radiation from the massive stars. The infrared image shows light captured by Spitzer's infrared array camera. Light with wavelengths of 8 and 5.8 microns (red and orange) comes mainly from dust that has been heated by starlight. Light of 4.5 microns (green) shows hot gas and dust; and light of 3.6 microns (blue) is from starlight.