Robotic Arm Camera (RAC)

built by the University of Arizona and Max Planck Institute, Germany

The RAC is attached to the Robotic Arm (RA) just above the scoop. The instrument provides close-up, full-color images of (1) the martian surface in the vicinity of the lander, (2) prospective soil and water ice samples in the trench dug by the RA, (3) verification of collected samples in the scoop prior to analysis by the MECA and TEGA instruments, and (4) the floor and side-walls of the trench to examine fine-scale texturing and layering.

By examining the color and grain size of scoop samples, scientists will better understand the nature of the soil and water-ice in the trench being dug by the RA. Additionally, floor and side-walls images of the trench may help determine the presence of any fine-scale layering that may result from changes in Martian climate.

RAC
Built for the Mars Surveyor 2001 Lander, the RAC provides close-up images of soil and water-ice samples. Image Credit: NASA/JPL.
The RAC is a box-shaped imager with a double Gauss lens system, commonly found in many 35 mm cameras, and a charged-coupled device similar to those found on many consumer digital cameras. Two lighting assemblies provide illumination of the target area. The upper assembly contains 36 blue, 18 green, and 18 red lamps and the lower assembly contains 16 blue, 8 green, and 8 red lamps. The RAC has two motors: one sets the lens focus from 11 mm to infinity and the other opens and closes a transparent dust cover. The instruments magnification is 1:1 at closest focus, providing image resolutions of 23 microns per pixel.

The RAC was originally built by a team at the University of Arizona and the Max Planck Institute for Solar System Research, Germany for the Mars Surveryor 2001 Lander missions. When the mission was cancelled, the camera was put into bonded storage at the Jet Propulsion Laboratory awaiting the RAC's future use in the Phoenix mission.