Mars rover hoping to yield more secrets, 1 year on

The dazzling success of NASA's rover Curiosity has paved the way for a human conquest of Mars, scientists say, almost one year after the groundbreaking probe first touched down on the Red Planet. Since it successfully alighted on the Martian surface on August 6, 2012, Curiosity has gathered and beamed back to Earth a treasure trove of information expected to be vital when a manned mission to Mars eventually takes place. Curiosity, roughly the size of a small 4x4 vehicle and weighing around a ton, has already ticked one of the most important boxes of its mission -- establishing beyond doubt that Mars' environment was capable of supporting microbial life in the distant past. That breakthrough in March means the rover's mission is likely to be extended beyond its provisional two-year mandate. "Successes of our Curiosity -- that dramatic touchdown a year ago and the science findings since then -- advance us toward further exploration, including sending humans to an asteroid and Mars," said NASA Administrator Charles Bolden. "Wheel tracks now will lead to boot prints later." Curiosity's nerve-jangling touchdown last year -- when the six-wheeled robot landed in the Gale Crater, roughly 10 kilometers from the foot of the planet's 5,000-meter high Mount Sharp, had also provided crucial encouragement for those hoping to one day mastermind a successful human mission. The complex nature of the landing showed that successfully landing heavier loads on the planet -- something that has been regarded as one of the major technological challenges of a manned mission -- is possible. "We have been extremely pleased so far this year," said Michael Meyer, the lead scientist of NASA's Mars Program. "In terms of contribution to general exploration it's a fantastic step forward because for one, the landing system is new. So that represents a way to get to the planetary surface. We put a metric ton on the surface. "The more we learn about Mars the better informed we will be to send humans in the future." Since it's arrival on Mars, Curiosity has provided more than 190 gigabits of data -- equivalent to around 45,600 songs stored in MP3 files -- while beaming back some 36,700 full images and 35,000 thumbnail images. The rover has also fired more than 75,000 laser shots to investigate the composition of the Martian surface while collecting and analyzing sample material from two rocks. The rover has traveled more than one mile (1.6 kilometers) and is heading towards Mount Sharp where NASA hopes it will yield more clues about the Red Planet's make-up. Curiosity's instruments and cameras enabled it to quickly determine the question of whether Mars could support microbial life, Meyer said. Shortly after landing, Curiosity detected clusters of pebbles and gravel formed by the flow of water in an ancient river bed. Analysis of rocks in the area then determined that the water which had once flowed was not salty or too acidic to prevent life. NASA is now sending Curiosity towards the distant peak of Mount Sharp, where scientists hope analysis of sedimentary layers will enable them to determine when Mars may have been suitable to support life. "If you find that multiple environments were habitable, it increases the likelihood that there was life on Mars," said John Logsdon, former director of the Space Policy Institute and a current member of NASA's advisory committee. "The mission has been remarkably successful. It's been pushing the envelope in both technical and human capabilities and it is something that everybody should be proud of," he added. Meyer meanwhile expressed optimism that Curiosity may even be able to detect more definitive signs of life during the year ahead. "Curiosity could make a major discovery, it has the capability to be very lucky," he said. "The instruments are specifically selected to determine whether or not at a certain time in the past Mars could support life," he explained. "But it does have the capability to measure organic (matter), so if there is a significant signature of life from the past it might be able to sort it out. "However any confirmation of past life or even life today will require another mission," said Meyer, noting that NASA plans to send a second rover to Mars -- "Curiosity 2" -- in 2020. Meanwhile, the Euro-Russian ExoMars robot, a rover which will also search for bio-signatures of Martian life, is scheduled for launch in 2018.