As extraterrestrial journeys go, it is not the most imposing challenge that science has faced. Yet the 400m journey on which the Martian rover Curiosity embarked last week is being watched with breathless attention by planetary experts.
The US$2.5 billion vehicle, the most sophisticated machine to visit another world, was sent to the Red Planet to provide data that could show Mars is, or was, capable of supporting life. This task will require the use of a battery of instruments — lasers to zap rocks, neutron beams to analyze soil and drills to break up samples — which will be put through their paces on this, the NASA craft’s first test drive.
Hence the tension at the Curiosity team’s headquarters at the Jet Propulsion Laboratory (JPL) in Pasadena, California. A failure of a key device on the car-sized rover’s jaunt through the red desert of Gale Crater, its landing site, could have devastating consequences, they say.
“I feel the burden of US$2.5 billion,” geologist John Grotzinger, leader of the 400-strong science team that runs Curiosity, told the journal Nature. “I feel the burden of the future of Mars exploration.”
Certainly, much is expected from the rover following its successful landing after being lowered to the Martian surface from a giant rocket-powered device called a sky crane on Aug. 6. Planetary exploration is now under severe budgetary stress in the US, the nation that has pioneered the field, and there are no detailed plans for future major missions. Hence the care being taken with Curiosity. When it comes to Martian exploration, this may be science’s only opportunity for a decade.
Certainly the Curiosity team is taking no chances in directing the craft on its way to Glenelg, the name given to its first target destination. This trip will take several weeks as the six-wheeled vehicle trundles, with infinite care, over the grayish-ocher soil of Mars.
“This drive really begins our journey toward the first major destination and it’s nice to see some Martian soil on our wheels,” mission manager Arthur Amador said.
The drive had proceeded beautifully, he said, “just as our rover planners designed it.”
Glenelg is considered important because three types of surface material meet there and mission scientists hope to compare these rocks, using the rover’s drill to investigate interesting-looking pebbles and boulders. A laser will vaporize slivers of rocks and analyze their chemical composition. A robot arm will pulverize pieces of stone, while the rover’s Sample Analysis of Mars (SAM) instrument has an oven in which soil and rock samples will be baked and tested for the presence of organic carbon.
“We have already tested quite a few instruments, including all 17 cameras on Curiosity,” deputy project scientist Ashwin Vasavada said. “However, the robot arm will be given a full test, as will the craft’s different drive modes.”
For the next two years or longer, Curiosity will use its instruments to carry out a chemical survey of the interior of Gale crater, a mission which it is hoped will show, once and for all, that the soil of Mars possesses organic materials — including amino acids and sugars, the building blocks of life — that could support living organisms.
“We will carry out a detailed chemical survey of all the different geological layers of Mars and so create an environmental history of the planet,” Vasavada said. “That will tell us what era most likely supported life during Mars’ history. From that, and from our other surveys of the planet, we will be able to pinpoint the most promising place to find life, or evidence of past life, on Mars.”