First launched a decade after its predecessors, Spaceborne Imaging Radar-C was coupled with the German-built X-Band Synthetic Aperture Radar to image Earth in three different wavelengths.
The instrument flew on two separate shuttle missions (STS-59 and STS-68, respectively) and collected data on terrestrial soil moisture content, ocean dynamics, volcanism and tectonic activity, and soil erosion and desertification.
The SIR-C/X-SAR (Shuttle Imaging Radar with Payload C / X-SAR) payload was a cooperative NASA/JPL, DARA/DLR, and ASI (Agenzia Spaziale Italiana) project flown on Space Shuttle Endeavour. The SIR-C/X-SAR project was part of NASA's Mission to Planet Earth. The experiment was the next evolutionary step in NASA's SIR (Spaceborne Imaging Radar) program that began with the Seasat Synthetic Aperture Radar (SAR) in l978, and continued with SIR-A in l98l and SIR-B in l984. It also represented a continuation of Germany's imaging radar program which started with the MRSE (Microwave Remote Sensing Experiment) flown aboard the Shuttle on the first SPACELAB mission in l983.
Photo of the SIR-C/X-SAR payload in the Shuttle bay. Credit: NASA