Mars rover ramps up for its first test drive (+video)
NASA's Curiosity rover has aced its first tests on Mars – twist wheel to the left, twist wheel to the right, extend robotic arm, pull it back – now it's heading out for a (nearly) 10-foot test drive.
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The rocket motors that cleared the bedrock may also have triggered a chain of events that rendered useless one set of wind sensors on Curiosity's weather station, sensors that worked as advertised during Curiosity's trip to Mars.Skip to next paragraph
In Pictures Exploring Mars with Curiosity
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Researchers in Spain and Finland supplied the weather station, whose instruments are housed in two small, offset booms that jut from Curiosity's mast. The wind sensors are built on small circuit boards that must be exposed to the elements in order to take the readings. One of those booms was located near the outside edge of Curiosity's deck as the arm sat folded against the deck for the launch and cruise phases of the mission.
The team noted something unexpected after Curiosity landed. Its deck was strewn with small pebbles. The team suspects that just before Curiosity was cut loose from the rocket-powered sky crane that lowered it to the surface, exhaust from the rocket motors kicked up the pebbles and deposited some of them on Curiosity's deck. Some of those flying pebbles may have struck this outward-facing circuit board, severing some of its fragile connections.
"We may never know what caused this damage," says Ashwin Vasavada, Curiosity's deputy project scientist.
Whatever is responsible for the wind sensor's failure, "the damage is permanent," he adds.
The team is now trying to figure out how to exploit the remaining wind sensor to best gather data on wind speed and direction both as science measurements and to support the operation of other instruments.
If Curiosity's weather wizards had a disappointing day or two, the same can't be said for the researchers using an instrument that will hunt for evidence of water under the surface as Curiosity ambles across the Martian surface.
The instrument, a neutron spectrometer dubbed DAN, was built in Russia and so far has checked out perfectly, says Igor Mitrofanov, a scientist with the Space Research Institute in Moscow and the instrument's lead scientist. The device bombards the surface beneath it with neutrons to a depth of a bit more than three feet, then measures how they are scattered. This scattering reveals the elements present in the layer of soil the neutrons penetrate.
The device is most sensitive to scattering in the top 20 inches or so. The water the team plans to hunt is tied up in hydrated minerals, rather than in ice, which would have a hard time persisting in Gale Crater, which is in Mars' equatorial region.
They should find plenty of hydrated minerals near the surface – evidence that the crater once held water. Data from a similar instrument aboard the Mars Odyssey orbiter, which is still circling the Red Planet, shows Gale Crater as a big patch of watery blue in a broader blue region where hydrated minerals abound. The blue is a false color the researchers added to help them analyze the surface composition. But there's nothing false about their expectations of finding evidence that deep in its past, Gale Crater once was host to a liquid deemed indispensable for organic life.