In Martian Life Evidence Search, Chemcam Laser Sets Its Sights On First Martian Target

The next tasks for ChemCam—the inaugural laser burst and spectral reading—will help scientists determine the integrity of the ChemCam system and the pointing capability of the rover’s mast, which supports ChemCam’s laser and telescope. Scientists and engineers from NASA’s Curiosity rover mission have selected ChemCam’s first target, a three-inch rock designated N-165 located near the rover.

“Rock N-165 looks like your typical Mars rock, about three inches (seven centimeters) wide and it’s about 10 feet away,” Wiens said. “We are going to hit it with 14 milliJoules of energy 30 times in 10 seconds. It is not only going to be an excellent test of our system, but it should be pretty cool too.”

The ChemCam system is one of 10 instruments mounted on the MSL mission’s Curiosity rover—a six-wheeled mobile laboratory that will roam more than 12 miles of the planet’s surface during the course of one Martian year (98 Earth weeks).

When ChemCam fires its extremely powerful laser pulse, it briefly focuses the energy of a million light bulbs onto an area the size of a pinhead. The laser blast vaporizes a small amount of its target up to seven meters (23 feet) away.

The resultant flash of glowing plasma is viewed by the system’s 4.3-inch aperture telescope, which sends the light down an optical fiber to a spectrometer located in the body of the rover. There the colors of the light from the flash are recorded, enabling scientists to determine the elemental composition of the vaporized material. ChemCam also has a high-resolution camera that provides close-up images of an analyzed location. It can image a human hair from seven feet away.

The ChemCam system is designed to capture as many as 14,000 observations throughout the mission.

The laser, telescope, and camera were provided by the French space agency, CNES, while the spectrometers, electronics, and software were built at Los Alamos National Laboratory, which leads the investigation. The spectrometers were developed with the aid of Ocean Optics, Incorporated, and Jet Propulsion Laboratory assisted with various aspects of development.

This image shows a closer view of the landing site of NASA’s Curiosity rover and a destination nearby known as Glenelg. Curiosity landed inside Gale Crater on Mars on Aug. 5 PDT (Aug. 6 EDT) at the blue dot. It is planning on driving to an area marked with a red dot that is nicknamed Glenelg. That area marks the intersection of three kinds of terrain. Starting clockwise from the top of this image, scientists are interested in this brighter terrain because it may represent a kind of bedrock suitable for eventual drilling by Curiosity. The next terrain shows the marks of many small craters and intrigues scientists because it might represent an older or harder surface. The third, which is the kind of terrain Curiosity landed in, is interesting because scientists can try to determine if the same kind of rock texture at Goulburn, an area where blasts from the descent stage rocket engines scoured away some of the surface, also occurs at Glenelg. 

The science team thought the name Glenelg was appropriate because, if Curiosity traveled there, it would visit the area twice — both coming and going — and the word Glenelg is a palindrome. After Glenelg, the rover will aim to drive to the base of Mount Sharp. 

These annotations have been made on top of an image acquired by the High Resolution Imaging Science Experiment on NASA’s Mars Reconnaissance Orbiter. 

Image credit: NASA/JPL-Caltech/Univ. of Arizo