Image of Saturn and us. The Earth-Moon system is visible as a bright blue point on the right side of the image above center and in the magnified view (Imaging Science Subsystem Narrow Angle Camera).

Stereo pair of cameras, each with a 45-degree field of view, is used to support rover ground navigation planning (Navcam).

The MRO MCS radiometer during final assembly prior to fitting of thermal blankets.

Diviner lunar radiometer.

"A picture is worth a thousand words." The first U.S. interplanetary mission, Mariner 2, carried no camera. Mariner 4's camera, crude by today's standards, took 21 (count 'em) pictures of Mars, which together revolutionized our understanding of that planet, while imaging only a small fraction of it in 1964. Mariner 9 took thousands of images in 1972, mapping 100% of Mars' surface. These pictures forced another complete re-write of textbooks with the discovery of ancient riverbeds, massive volcanoes, rift valleys, dune fields, and more. Still, cameras were not considered true "science instruments," and many thought their value lay almost entirely with public relations.

Times have changed! Cameras are considered essential science instruments on every Solar System exploration mission. Their functions have broadened, and sophistication deepened. Planetary geology, meteorology, and other disciplines owe their existence to the data returned by a wide variety of cameras, ranging from the ultraviolet, through the visible, and out into the thermal infrared regions of the electromagnetic spectrum. Close to a dozen separate specialized cameras are being built for the roving Mars Science Laboratory, to be launched in 2009.

Astronomy has been revolutionized by the images taken from telescopes orbiting Earth, above our obscuring and absorbing atmosphere.

Earth itself is the object of many more specialized cameras that collect, along with other instruments, a heretofore unimagined data set about our planet, our atmosphere, and our influence on this dynamic environment.

People at JPL have built more cameras for space exploration, of a greater variety, than at any other institution. Some recent ones are sampled below.

Hazard Avoidance Cameras (Hazcams)

Mounted on the lower portion of the front and rear of the rover, these black-and-white cameras will use visible light to

capture three-dimensional (3-D) imagery. This imagery safeguards against the rover getting lost or inadvertently

crashing into unexpected obstacles, and works in tandem with software that allows the rover make its own safety

choices and to "think on its own."

The cameras each have a wide field of view of about 120 degrees. The rover uses pairs of Hazcam images to map

out the shape of the terrain as far as 3 meters (10 feet) in front of it, in a "wedge" shape that is over 4 meters wide

(13 feet) at the farthest distance. The cameras need to see far to either side because unlike human eyes, the

Hazcam cameras cannot move independently; they are mounted directly to the rover body.

Navigation Cameras (Navcams)

Mounted on the mast (the rover "neck and head"), these black-and-white cameras will use visible light to gather panoramic, three-dimensional (3D) imagery. The navigation camera unit is a stereo pair of cameras, each with a 45-degree field of view that will support ground navigation planning by scientists and engineers. They will work in cooperation with the hazard avoidance cameras by providing a complementary view of the terrain.

Diviner

The objective of Diviner is to measure lunar surface temperatures at scales that provide essential information for future surface operations and exploration. The temperature of the lunar surface and subsurface is a critical environmental parameter for future human and robotic exploration. While the Apollo missions were all targeted to equatorial landing sites and were only conducted during the lunar day. NASA's new lunar exploration program will involve exploration of a much wider range of latitudes, and astronaut stays of longer than two weeks. Both types of missions involve considerably more challenging thermal environments, and will benefit greatly from a comprehensive global thermal mapping dataset that Diviner will provide. Orbital thermal mapping measurements provide detailed information on key engineering parameters such as surface and subsurface temperatures, as well as valuable constraints on landing hazards such as rough terrain or rocks.

Measurement goals of the Diviner Lunar Radiometer Experiment.

• Map global day/night surface temperature
• Characterize thermal environments for habitability
• Determine rock abundances at landing sites and globally
• Identify potential polar ice reservoirs
• Search for near-surface and exposed ice

The Diviner instrument is a multi-channel solar reflectance and infrared filter radiometer The major elements of the Diviner radiometer are shown in Figure 1.2-1. Diviner is a nine-channel filter radiometer that utilizes uncooled thermopile detector arrays. Diviner's spectral channels are distributed between two identical, boresighted telescopes, and an articulated elevation/azimuth mount allows the telescopes to view the Lunar surface, space, and calibration targets. The instantaneous field-of-view (FOV) response of each channel is defined by a linear, 21-element, thermopile detector array at the telescope focal plane, and its spectral response is defined by a focal plane bandpass filter.

The Diviner structure consists of an instrument optics bench assembly (OBA), an elevation/azimuth yoke, and an instrument mount. The OBA contains all of the instrument optical subassemblies, and is suspended from the yoke. Elevation and azimuth motors mounted on the yoke drive instrument articulation. The OBA is temperature controlled, and internal temperature gradients are minimized by design. Radiometric calibration is provided by views of blackbody and solar targets mounted on the yoke. The electronics subassemblies control signal processing, instrument operation and articulation, command processing, and data processing and are distributed between the OBA and the yoke.

David Paige from Earth and Space Science Dept., University of California Los Angeles is the Principal Investigator for Diviner.