Nasa's Curiosity Rover Zaps Mars Rock Called Coronation

The 7cm Coronation rock offered a smooth face to Curiosity's laser instrument (ChemCam)

Nasa's Curiosity rover has zapped its first Martian rock.

The robot fired its ChemCam laser at a tennis-ball-sized stone lying about 2.5m away on the ground.

The brief but powerful burst of light from the instrument vapourised the surface of the rock, revealing details of its basic chemistry.

This was just target practice for ChemCam, proving it is ready to begin the serious business of investigating the geology of the Red Planet.

It is part of a suite of instruments on the one-tonne robot, which landed two weeks ago in a deep equatorial depression known as Gale Crater.

Over the course of one Martian year, Curiosity will try to determine whether past environments at its touchdown location could ever have supported life.

The US-French ChemCam instrument will be a critical part of that investigation, helping to select the most interesting objects for study.

The inaugural target of the laser was a 7cm-wide rock dubbed "Coronation" (previously N165).

It had no particular science value, and was expected to be just another lump of ubiquitous Martian basalt, a volcanic rock.

Its appeal was the nice smooth face it offered to the laser.

ChemCam zapped it with 30 pulses of infrared light during a 10-second period.

Each pulse delivered to a tiny spot more than a million watts of power for about five billionths of a second.

The instrument observed the resulting spark through a telescope; the component colours would have told scientists which atomic elements were present.

"We got a great spectrum of Coronation - lots of signal," said ChemCam principal investigator Roger Wiens of Los Alamos National Laboratory, New Mexico.

"Our team is both thrilled and working hard, looking at the results. After eight years building the instrument, it's pay-off time."

The first science target for ChemCam will be bedrock exposed on the ground next to Curiosity by the rocket-powered crane used to lower the vehicle to the crater floor on 6 August (GMT).

Exhaust from this descent stage scattered surface grit and pebbles to reveal a harder, compact material underneath.

The crane made four scour marks in the ground - two either side of the rover. These have been dubbed Burnside, Goulburn, Hepburn and Sleepy Dragon - names taken from ancient rock formations in Canadian North America.

Goulburn Scour will be zapped by ChemCam once the mission team has reviewed fully the Coronation performance and results.