The star-forming nebula W51 is one of the largest "star factories" in the Milky Way galaxy. Interstellar dust blocks the visible light emitted by the region, but it is revealed by NASA's Spitzer Space Telescope, which captures infrared light that can penetrate dust clouds.

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology, also in Pasadena. Caltech manages JPL for NASA.

More information on Spitzer can be found at its website:

http://www.spitzer.caltech.edu/