Bright Lights, Green City

Two extremely bright stars illuminate a greenish mist in this and other images from the new "GLIMPSE360" survey from NASA's Spitzer Space Telescope. This fog is comprised of hydrogen and carbon compounds called polycyclic aromatic hydrocarbons (PAHs), which are found right here on Earth in sooty vehicle exhaust and on charred grills. In space, PAHs form in the dark clouds that give rise to stars. These molecules provide astronomers a way to visualize the peripheries of gas clouds and study their structures in great detail. They are not actually "green;" but are color coded in these images to let scientists see their glow in infrared.

Strange streaks -- likely dust grains that lined up with magnetic fields -- distort the star in the top left. The fairly close, well-studied star GL 490 gleams in the middle right. The new observations have revealed several small, blobby outflows of gas from nearby forming stars, which indicate their youth. Such outflows are a great way to target really young, massive stars in their very earliest, hard-to-catch stages.

This image is a combination of data from Spitzer and the Two-Micron All-Sky Survey (2MASS). The Spitzer data was taken after Spitzer's liquid coolant ran dry in May 2009, marking the beginning of its "warm" mission. Light from Spitzer's remaining infrared channels at 3.6 and 4.5 microns has been represented in green and red, respectively. 2MASS observations at 2.2 microns are blue.