The material that forms W40’s wings was ejected from a dense cluster of stars that lies between the wings in the image. The hottest, most massive of these stars, W40 IRS 1a, lies near the center of the star cluster. W40 is about 1,400 light-years from the Sun, about the same distance as the well-known Orion nebula, although the two are almost 180 degrees apart in the sky. Launched on August 25, 2003, NASA’s Spitzer Space Telescope’s goal was to provide a unique, infrared view of the universe and allow us to peer into regions of space that are hidden from optical telescopes. It was the final mission in NASA’s Great Observatories Program — a family of four space-based observatories, each observing the Universe in a different kind of light. The other missions in the program include the visible-light Hubble Space Telescope (HST), Compton Gamma-Ray Observatory (CGRO), and the Chandra X-Ray Observatory (CXO). Its mission ended on January 30, 2020.
