In a flawless, triumphant technological tour de
force, a plutonium-powered rover the size of a small car was lowered at
the end of 25-foot-long cables from a hovering rocket stage onto Mars
early on Monday morning.
Curiosity Touches Down on Mars
Precision Landing on Mars
One of the first test images from NASA’s Mars
Curiosity rover that helped signal that everything was operational.
NASA's Mars Curiosity rover and its parachute were
captured in this image from the High-Resolution Imaging Science
Experiment. The inset shows a cutout of the rover stretched to avoid
saturation.
The rover, called Curiosity, ushers in a new era of exploration that
could turn up evidence that the Red Planet once had the necessary
ingredients for life — or might even still harbor life today. NASA and
administration officials were also quick to point to the success to
counter criticism that the space agency had turned into a creaky
bureaucracy incapable of matching its past glory.
“If anybody has been harboring doubts about the status of U.S.
leadership in space,” John P. Holdren, the president’s science adviser,
said at a news conference following the landing, “well, there’s a
one-ton, automobile-size piece of American ingenuity, and it’s sitting
on the surface of Mars right now.”
Only one other country, the Soviet Union, has successfully landed
anything on Mars, and that spacecraft, Mars 3 in 1971, fell silent
shortly after landing.
Curiosity is far larger than earlier rovers and is packed with the most
sophisticated movable laboratory that has ever been sent to another
planet. It is to spend at least two years examining rocks within the
96-mile crater it landed in, looking for carbon-based molecules and
other evidence that early Mars had conditions friendly for life.
As the spacecraft carrying the Curiosity sped toward its destination on
Sunday, the pull of Mars’s gravity accelerating it to more than 13,000
miles per hour, NASA officials tried to tamp down concerns that a crash
would entirely derail future plans.
“A failure is a setback,” said Doug McCuistion, the Mars exploration program director. “It’s not a disaster.”
Meanwhile, mission managers warned that glitches with interplanetary
communications could leave them not knowing Curiosity’s fate for hours
or days. They emphasized that, while the planning, testing and design
had been careful and methodical, any attempt to land on Mars carried the
risk of failure.
“These things are really hard to do,” Mr. McCuistion said.
The Curiosity landing seemed particularly risky. Engineers chose not to
use the tried-and-true landing systems, neither the landing legs of the
Viking missions in 1976 nor the cocoons of air bags that cushioned the
two rovers that NASA placed on Mars in 2004. Those approaches, they
said, would not work for a one-ton vehicle.
Instead, for the final landing step, they came up with something novel
that they called the sky crane maneuver. The rover would be gently
winched to the surface from a hovering rocket stage.
As the drama of the landing unfolded, each step proceeded without flaw.
The capsule entered the atmosphere at the appointed time, with thrusters
guiding it toward the crater. The parachute deployed. Then the rover
and rocket stage dropped away from the parachute and began a powered
descent toward the surface, and the sky crane maneuver worked as
designed.
“Touchdown confirmed,” Allen Chen, an engineer in the control room, said
at 1:32 a.m. Eastern time, followed by cheers, hugs and high-fives.
Two minutes later, the first image popped onto video screens — a grainy,
64-pixel-by-64-pixel black-and-white image that showed one of the
rover’s wheels and the Martian horizon. A few minutes later, a clearer
version appeared, and then came another image from the other side of the
rover.
“That’s the shadow of the Curiosity rover on the surface of Mars,”
Robert Manning, the chief engineer for the project, gushed in awe.
Even more photos were beamed back a couple of hours later.
“Curiosity’s landing site is beginning to come into focus,” said John P.
Grotzinger, the project scientist, in a NASA news release. In one
photograph, the rim of the crater is seen in the distance. “In the
foreground, you can see a gravel field,” Dr. Grotzinger said. “The
question is, where does this gravel come from? It is the first of what
will be many scientific questions to come from our new home on Mars.”
Over the first week, Curiosity is to deploy its main antenna, raise a
mast containing cameras, a rock-vaporizing laser and other instruments,
and take its first panoramic shot of its surroundings.
NASA will spend the first weeks checking out Curiosity before embarking
on the first drive. The rover will not scoop its first sample of Martian
soil until mid-September at the earliest, and the first drilling into
rock is not expected until October or November.
The successful landing helps wash away the mission’s troubled
beginnings. Originally it was to cost $1.6 billion and was scheduled to
launch in fall 2009, but it encountered a cascade of technical hurdles
and cost overruns.
NASA officials faced a difficult choice: to rush to meet the launch date
or miss it, waiting 26 months until the next time that Mars and Earth
lined up in the proper positions.
They chose to wait, even though that added hundreds of millions of
dollars to the price tag, bringing it to $2.5 billion.
Charles Elachi, director of the NASA Jet Propulsion Laboratory, which
operates Curiosity and many of the other planetary missions, said it was
well worth the money and compared the night’s exhilaration to an
adventure movie.
“This movie cost you less than seven bucks per American citizen, and look at the excitement we got,” Dr. Elachi said.
Even at the late hour, NASA’s Web sites collapsed under the throngs of
people across the Internet attempting to look at the new Mars photos.
“Tomorrow we’re going to start exploring Mars,” Dr. Elachi said. “And
next week and next month and next year, we’ll be bringing new
discoveries every day, every week, to all of you.”
Because Curiosity is powered by electricity generated from the heat of a
chunk of plutonium, it could continue operating for years, perhaps
decades, until it finally wears out.
source : http://www.nytimes.com/2012/08/06/science/space/curiosity-rover-lands-safely-on-mars.html
Tag :
Astronomy
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