The Context Camera, called CTX, provides a big-picture, background view of the terrain around smaller rock and mineral targets that are studied by other cameras on the Mars Reconnaissance Orbiter.
|Main Job||To help provide a context for high-resolution analysis of key spots on Mars provided by HiRISE and CRISM.|
|Mass||6.6 pounds (3 kilograms)|
|Power||7 Watts (imaging); 5 Watts (idling)|
|Data Return||Includes a 256 MB DRAM buffer, so that it can acquire pictures that have downtrack lengths greater than 160 kilometers (99 miles).|
|Color Quality||Black and white (grayscale); a broad band of visible light from 500 to 800 nanometers in wavelength.|
|Image Size||5064 pixels-wide x varying length (due to a 256 MB DRAM buffer, so that it can acquire pictures that have downtrack lengths greater than 99 miles (160 kilometers).|
|Image Resolution||~20 feet (6 meters) per pixel scale from an altitude of 186 miles (300 km) over a swath 18.6 miles (30 km) wide.|
|Focal Length||13.7 inch (350 mm) focal length|
|Focal Ratio and Field of View||f/3.25, IFOV of 0.001 degrees (20 μrad) and a FOV of 6 degrees|
As its name suggests, CTX provides the wider context for the data collected by the other two instruments. Scientists examine details of rocks and mineral fields with the other instruments, while CTX provides a bigger-picture view of the terrain.
Together HiRISE, CRISM, and CTX are an extremely powerful tool set. For example, many of the layered terrains observed by the Mars Orbital Camera on the Mars Global Surveyor spacecraft could be water-deposited sediments. They could also be layers of volcanic lavas, ash, or wind-deposited sediments. By combining information about small-scale layers from HiRISE, the geologic context from CTX, and the mineralogical information from CRISM, scientists can distinguish between these possibilities.
From 400 kilometers (250 miles) above Mars, CTX takes images spanning 30 kilometers (almost 19 miles) of terrain. The camera has a resolution of 6 meters per pixel.
The team lead and supplier of CTX is Mike Malin from Malin Space Science Systems.
Visit the instrument site: Context Camera Instrument Site