The InfraRed Spectrograph (IRS) was one of three focal plane instruments on the Spitzer Space Telescope. It consisted of four separate modules (Short-Low, Short-High, Long-Low, Long-High) which provided low (R~60-130) and moderate (R~600) resolution spectroscopic capabilities from 5.2 to 38 microns. Spectra could be obtained in either staring or mapping mode. In addition, the IRS provided imaging in two filters (13-18 and 18-26 microns) and onboard software to autonomously identify point sources and accurately place them (by offsetting the telescope) in any of the IRS slits. This Peak-up mode was also used to obtain calibrated images of the sky at 16 and 22 microns over a 1x1 arcminute field of view, providing the only imaging capability on Spitzer between 8 and 24 microns.

The IRS was built by Ball Aerospace under contract to JPL and Cornell University based on designs and prototypes constructed at Cornell under principal investigator James R. Houck.

IRS Pocket Guide (PDF, 223 KB)