Barreling in from space at thirteen thousand miles an hour before stopping a mere 25 feet above the ground would make anyone want to catch their breath, and NASA’s Curiosity rover is no exception. Now that the Seven Minutes of Terror is over, the compact-car-sized biochemistry lab is spending its first two weeks doing the same thing you might do after stepping off a hair-raising roller coaster: making sure its parts are where they’re supposed to be and functioning correctly.
That means daily surprises, as technicians at the Jet Propulsion Laboratory in La Canada Flintridge in California, raise antennas, activate cameras, and gradually bring systems on line. Among the early treats: 297 black-and-white thumbnail pictures, which NASA processed into a low-quality video showing the final two-and-a-half minutes of Curiosity’s stomach-churning plunge through the Martian atmosphere. The thumbnails, though grainy, show the protective heat shield dropping away, the bumps from the rover’s parachute descent, and dust kicking up as cables lowered the rover to the Martian surface. Scientists expect to have a full-resolution video from Curiosity’s descent imager in a few days.
The rover also sent a new postcard: the first full-color landscape image of Curiosity’s Gale Crater home, taken as part of a focus test to check one of the cameras mounted on the rover’s mast. Until this week the camera, called the Mars Hand Lens Imager (MAHLI), hadn’t moved its focal components since July of 2011— four months before Curiosity launched. Even now, with the mast still tucked horizontally atop the rover’s front left shoulder, the camera’s initial focus test offers a tempting glimpse of the north wall of the rim at Gale Crater.
But that’s just a small taste of what this particular camera, one of seventeen aboard Curiosity, will provide once the mast is lifted and extended, especially once the camera’s clear dust covers lift away. “It’s so awesome because we can put this camera anywhere,” says Ken Edgett of Malin Space Science Systems in San Diego, which operates the camera. “Up, down, within an inch of the soil, underneath the rover, anywhere. It’ll extend up above the mast to give us the giraffe’s-eye view, or give us the oblique, dog’s-eye view across the Martian surface. This camera can look wherever we want.”
Many of this week’s most captivating images haven’t come from Curiosity, but a high-resolution camera aboard the Mars Reconnaissance Orbiter, another player on NASA’s robotic exploration team. One day after capturing a stunning shot of Curiosity parachuting towards Martian surface, the Orbiter executed an unusual forty-degree roll to deliver a fascinating “crime scene” image taken by a high-resolution camera aboard the Mars Reconnaissance Orbiter some 186 miles above the surface. The view offers a look at the pimple-sized rover in relation to the locations where Curiosity’s heat shield, parachute, back shell, and ballyhooed sky crane crash-landed after dropping away from the rover during its descent.
Simply put, they’re all in the same Gale Crater neighborhood. The heat shield is farthest from Curiosity, about three-quarters of a mile away. Both the back shell and sky crane wound up about four-tenths of a mile from the rover. Of particular visual interest is a jagged pattern in the Martian soil to one side of the downed sky crane. “Those dark areas downrange are the disturbed dust,” says Sarah Milkovich, a JPL scientist. “It’s the same pattern we see when we have meteorites forming impact craters on the surface of a planetary body.” Since the impacts from the spacecraft’s components kicked up plenty of dust as well, Milkovich says future images should have even greater resolution. The Orbiter will again aim its cameras at Gale Crater in a few days, possibly for color photos.
All of this is just prep work, however. In the coming two weeks, JPL engineers will conduct numerous systems checks while the science team decides where, if anywhere, they want to go. “It’s designed as a go-to mission, but the place where we landed looks really interesting,” says project scientist John Grotzinger. “We have millions of years of Mars history to sample, and it starts where we landed, so we don’t really want to roll out of there.” One reason scientists chose to land at Gale Crater is the fact it’s surface soil is part of what geologists call an alluvial fan, meaning it’s the site where ancient water shed debris from the crater’s rim and nearby Mount Sharp. “It could be a jackpot,” Grotzinger says. “We studied Mount Sharp first, but now that we’re starting in on the ellipse we’re realizing this place is awesome.”
But even interplanetary rovers in awesome locations have to tackle mundane chores, and Curiosity’s turn begins this weekend when the rover waits for a software upgrade. Much like we change operating systems on a home PC, Curiosity will spend parts of four days upgrading its dual computers. There are no Lions or Windows on Mars, however. Curiosity is switching from the blandly named R9 operating system to, yes, the R10. The upgrade removes much of the computer’s entry, descent and landing functions, which are no longer needed, and replaces them with software for controlling the robotic arm and sample analysis. “Once we get on that new OS we can start flexing our arm and checking the surface,” says mission manager Michael Watkins. No connection speed issues for Curiosity’s upgrade; the rover already downloaded the new software while en route to Mars.
Curiosity may also begin rolling next week, but not far. “We’ll probably do a ‘test bump’ with some wheel rotation,” Watkins says. The wheels won’t move much— maybe one full rotation, which amounts to no more than three feet of movement. It’s all part of the “slow and go” mantra that scientists say is a luxury they’ve never had during a Mars mission. “It’s a learning experience for us too,” says Watkins. “In the meetings we’re always thinking we need to go fast because, with the other rovers, we had tasks we tried to get to right away. But, this time, we’re saying from the start: ‘We’ve got two years, let’s use that rover to our full capability.’”
Or, as Edgett says, “it’s going to go on, and on, and on.” He means it as a joke, but there’s at least a chance that he’s right, and that Curiosity will continue throwing treats our way for years to come.
Martian Vistas: A Look at Curiosity’s New Home:
A towering dust devil casts a serpentine shadow over the Martian surface in this stunning, late springtime image of Amazonis Planitia. The length of the shadow indicates that the dust plume reaches more than eight hundred meters, or half a mile, in height. Mars's thin atmosphere— less than one percent that of Earth's— can still whip up considerable winds.
This two-and-a-half mile diameter crater appears relatively fresh but, with little erosion or upheaval on Mars, and no evidence of an extremely recent meteor hit, "fresh" is a relative term.
Mars has extremely large temperature changes from winter to summer compared to the Earth. It gets cold enough to freeze carbon dioxide out of the atmosphere during the winter, but this ice is unstable when the warmer summer arrives and forces it to sublimate (transform directly back into a gas).
Most of the dunes visible in this image are what's known as barchan dunes, where the steep slip face is between two "horns" that point downwind.
This color image of Santa Maria Crater, with the Opportunity rover perched on the southeast rim (arrow). Rover tracks are clearly visible to the east. Opportunity and its twin Spirit landed on Mars in 2004.
An approximately eight-hundred-mile-diameter depression from which enormous cataclysmic releases of ground water are thought to have exploded onto the surface of Mars long ago. Mars is filled with surface depressions and riverbeds carved and otherwise formed by ancient water flows.
Sensitive to subtle shifts in wind circulation patterns and wind strengths, Martian sand dunes are shaped just like those on Earth. On both worlds, the subtleties provide clues to the sedimentary history of the surrounding terrain.
Rico says that, shy of the discovery of actual aliens, this is the coolest...
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