Marte

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http://www.sciencenewsforkids.org/2012/08/curiosity-lands-on-mars/

Curiosity lands on Mars!
By Janet Raloff / August 8, 2012 On August 5, after a journey lasting more than 8 months, a carlike rover carefully settled down onto the surface of Mars. The vehicle is basically a science lab. Its mission: to search for evidence that the Red Planet might once have hostedlife Artist’s drawing of Curiosity on the Martian surface. Credit: NASA — even if the organisms were only one-celled microbes. The first stage of this mission — the landing — is “an amazing achievement,” observes Charles Bolden. He runs the National Aeronautics and Space Administration, or NASA, which built and delivered the vehicle to Mars. NASA named the robotic cruiser Curiosity. The six-wheeledall-terrain vehicle weighs 900 kilograms (about 1 U.S. ton). Roughly 2.8 meters (9 feet) long, it carries 10 research instruments. Seventeen separate cameras (including one on the rover’s belly, to scan below it) will survey the landscape and record experiments. The rover’s primary goal “is to explore habitable environments,” says project scientist John Grotzinger of the Jet Propulsion Laboratory(JPL) in Pasadena, Calif. By habitable, he means an environment that can support life. His team interprets that to mean there must be water, carbon — a basic building block of life on Earth — and food to fuel an organism’s activities, he told Science News.

Curiosity is not the first rover NASA has sent to Mars, but it is the biggest and has the most research instruments. Think of it as arolling laboratory that can travel 200 meters (656 feet) per day, up and over obstacles 65 centimeters (25 inches) high. Several years ago, NASA scientists began considering the best place for Curiosity to conduct its experiments. Last year, the researchers chose Gale Crater. So that’s where the rover landed.

A towering peak — Mount Sharp — rises from the center of this basin 150 kilometers (93miles) wide. Curiosity will spend two years motoring around and exploring the crater floor. The rover will be powered by energy given off by the decay of plutonium, a radioactive element. But probing the mountain will be the vehicle’s primary focus. At roughly 5 kilometers (16,400 feet), Sharp rises higher above the landscape than does any mountain in the continental United States. It’s built fromlayer upon layer of mineral-rich materials. Some clays in it would seem to have required water to form. So as Curiosity moves by, it will shoot out a laser beam at the mountain and then direct onboard chemical samplers to “taste” the vaporized rock. Another onboard device can drill into rock, pulverizing it into a fine powder for the rover’s chemical samplers to taste. Searching for life Thosesamplers will decipher the rocks’ chemical makeup. The recipes might establish whether any of these materials could have supported life. Shortly before the rover touched down, Science News reporter Nadia Drake spoke with JPL director Charles Elachi. He explained that scientists are “pretty convinced that Mars did have an ocean a few billion years ago.” An ancient sea would indicate that the temperatureon the Red Planet should have been similar to Earth’s. And that, he says, almost immediately raises the question: “Could life have evolved on Mars?” And if it could, he asks: “Did life evolve? How far did it evolve? And where is it now?” There’s no reason to suspect Earth is the only place to host life, Elachi told Drake. “I’m pretty sure life is there across the universe,” he said. “But as ascientist, you have to prove it.”

A satellite orbiting Mars captured this photo of a parachute slowing Curiosity’s descent to the surface of the Red Planet on August 5. (The image at right is a zoomed-in version.) Credit: NASA

He cautions that Curiosity won’t actually be searching for life (although if it found a good candidate, its cameras would surely try to snap glamour shots to thrill...