NASA’s Mars rover Curiosity has already fired its laser over 500 times as it studies its surroundings as engineers at the Jet Propulsion Laboratory (JPL) calibrate its sensors. In a classic example of “waste not, want not” Curiosity concentrated its activity on a patch of rocks that were uncovered by the rocket backwash of the sky crane that delivered the unmanned explorer to the Martian surface on August 6.

The outcrop of rocks, designated “Goulburn,” is about 16 to 20 feet (5 to 6 m) from where Curiosity landed and is of particular interest to scientists because the sky crane’s rocket blast cleared the patch of dust, allowing the laser a clean shot at the rocks. The results have been welcomed by the mission control at JPL.

“The spectrum we have received back from Curiosity is as good as anything we looked at on Earth,” said Los Alamos National Laboratory planetary scientist Roger Wiens, Principal Investigator of the ChemCam Team. “The entire MSL (Mars Science Laboratory) team was very excited about this and we popped a little champagne.”

Photo mosaic of rocks exposed by sky crane's rockets and then zapped by ChemCam (Image: NASA/JPL)

ChamCam is a suite of instruments housed partly on top of the rover’s mast and includes a telescope, the laser and a remote micro-imager provided by the French government space agency, CNES. A fiber-optic cable runs from the mast down to the three spectrometers inside the rover used to analyze the vaporized rocks. When the laser hits a rock, some of the target flashes into a bright plasma, the light of which the spectroscopes can use to detect various elements by their color spectra.

The tricky bit for the scientists was that the Martian atmosphere is 1/100th the pressure of Earth’s. This means that the plasma bursts wouldn't be as bright, so before heading to Mars, ChemCam had to be tested in a Mars simulator to allow for the difference. It also provided scientists with a set of spectrographs that they can compare to the data returned by Curiosity to make sure that ChemCam is operating properly.

These test shots are the first of 14,000 that ChemCam is scheduled to make over the next two years. According to NASA, Curiosity’s next task will be a second short drive to test the rover’s systems.

Source: Los Alamos National Laboratory