Viewed from below, a Boeing Delta II rocket is lifted up the launch tower on Launch Complex 17-B, Cape Canaveral Air Force Station. The rocket is the launch vehicle for the Space Infrared Telescope Facility. SIRTF will obtain images and spectra by detecting the infrared energy, or heat, radiated by objects in space between wavelengths of 3 and 180 microns (1 micron is one-millionth of a meter). Most of this infrared radiation is blocked by the Earth's atmosphere and cannot be observed from the ground. Consisting of an 0.85-meter telescope and three cryogenically cooled science instruments, SIRTF is one of NASA's largest infrared telescopes to be launched. Its highly sensitive instruments will give a unique view of the Universe and peer into regions of space that are hidden from optical telescopes on the ground or orbiting telescopes such as the Hubble Space Telescope.