Since its launch in August 2003, says Robert Kennicutt, an astronomer at the University of Arizona, NASA's Spitzer Space Telescope "has opened up half the universe to us." In the process ...

This side-by-side image compares the resolution of a distant galaxy imaged by the Spitzer Space Telescope in the near-infrared, left, to a simulated image from the Webb telescope. Disclaimer ...

The Hubble is just one of NASA's orbiting "great observatories." The group also includes the Spitzer Space Telescope and the Chandra X-ray Observatory. Spitzer is an infrared orbiting telescope ...