The following images and captions are from the JPL Public Information Office.
These images are made by taking (in most cases) multichannel radar images and assigning the colors red, green, and blue to three of the channels. An example of how this is done is shown here. (If you autoload images, you will have to load about 750K)
Mt. Pinatubo comparison
Colombian volcano
Galapagos Islands
Galeras Volcano
Isla Isabela 3-D
Kamchatka Peninsula, Russia
Kilauea, Hawaii
Mammoth, California
Mammoth, California 3-D
Mt Pinatubo, Philippines
Unzen volcano, Japan
Colima Volcano, Mexico
Central Africa gorilla habitat
Kliuchevskoi Volcano, Russia
Kliuchevskoi Volcano optical/radar
comparison
Maly Semlyachik Volcano, Russia
Mammoth Mountain, California
Mauna Loa, Hawaii
Rabaul volcano, New Guinea
Mt. Rainier, Washington
Taal volcano, Philippines
SIR-C/X-SAR radars illuminate Earth with microwaves allowing detailed observations at any time, regardless of weather or sunlight conditions. SIR-C/X-SAR uses three microwave wavelengths: L-band (24 cm), C-band (6 cm) and X-band (3 cm). The multi-frequency data will be used by the international scientific community to better understand the global environment and how it is changing. The SIR-C/X-SAR data, in conjunction with aircraft and ground studies, will give scientists clearer insights into those environmental changes which are caused by nature and those changes which are induced by human activity. SIR-C was developed by NASA's Jet Propulsion Laboratory. X-SAR was developed by the Dornier and Alenia Spazio companies for the German space agency, Deutsche Agentur fur Raumfahrtangelegenheiten (DARA), and the Italian space agency, Agenzia Spaziale Italiana (ASI).