NASA Preps Mars Probe for Launch
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From NPR News, this is ALL THINGS CONSIDERED. I'm Michele Norris.
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And I'm Melissa Block.
With the shuttle Discovery safely back on Earth, NASA's getting ready for another voyage into space, only there won't be any astronauts this time. Tomorrow morning the agency plans to launch its unmanned Mars reconnaissance orbiter from Cape Canaveral. If all goes well, the ship will reach Mars in about seven months and circle the planet for several years. As NPR's Jon Hamilton reports, part of its mission is to learn whether life could have existed on the red planet.
JON HAMILTON reporting:
Life depends on water, so this trip to Mars is all about water. NASA already has two rovers rolling across the planet's hills and craters. These vehicles have sent back some of the strongest evidence yet that water once flowed on Mars. Richard Zurek from NASA's Jet Propulsion Laboratory is one of the scientists who spoke with reporters this week about the mission. He says one important task for the new mission will be finding out whether Mars has a lot of water or just a little.
Mr. RICHARD ZUREK (Jet Propulsion Laboratory, NASA): There is ice present in much of the upper yard or so of the Mars surface over much of the planet. Now it's not everywhere, but it is extensive. And we want to know whether or not that layer of ice is just a thin layer or whether it represents just the tip of an iceberg, so to speak, and extends much deeper.
HAMILTON: Finding lots of water would improve the odds that Mars once had life. So the orbiter will scan the planet with a special radar provided by the Italian Space Agency. From an altitude of about 200 miles, this radar will search for ice buried hundreds or thousands of feet beneath the planet's surface.
Another job for the new orbiter will be to look for evidence that the water on Mars was once liquid. The shape and composition of rocks on the planet surface could provide clues, but they're difficult to study because they're covered with a layer of martian dust. Scott Murchie of Johns Hopkins University says NASA appears to have a solution, a spectrometer that uses infrared light.
Mr. SCOTT MURCHIE (Johns Hopkins University): And it can see through that fine layer of dust at the underlying rocks that occur on the surface, and this is literally seeing Mars in a new light.
HAMILTON: The rover Spirit landed in what might be a former lake bed. Now scientists are looking for more signs of liquid water, perhaps even evidence of ancient hot springs. Murchie says that means scanning the surface for deposits of certain minerals.
Mr. MURCHIE: Specific kinds of minerals like sulfates and clays that leave a mineral record that can go back and be investigated to give you information and insight into what Mars was like in the very ancient time, three to four billion years ago, when these deposits formed.
HAMILTON: The orbiter won't land on Mars, but it will try to find good landing sites for future spacecraft. That's where the new orbiter's high-powered telescope comes in. Alfred McEwen of the University of Arizona says it will provide the first pictures of Mars clear enough to show whether there are dangerous boulders at the potential landing sites. The telescope also will help future vehicles avoid other hazards, like the thick dust that caused one of the current rovers to bog down temporarily.
Mr. ALFRED McEWEN (University of Arizona): We can actually see the terrain in enough detail to make some pretty good estimations of how trafficable the terrain is for rovers, so we can really plan out future exploration on the surface.
HAMILTON: If the new orbiter works as expected, it will send unprecedented amounts of information back to Earth. One NASA official said the current information pipeline from Mars is like a drinking straw. With the new orbiter, he says, it will be more like a fire hose. Jon Hamilton, NPR News.