After eight years of planning and eight months of
interplanetary travel, NASA's Mars Science Laboratory pulled off a
touchdown of Super Bowl proportions, all by itself. It even sent
pictures from the goal line.
Watch Video of Successful Landing of CURIOSITY ROVER
The spacecraft plunged through Mars' atmosphere, fired up a
rocket-powered platform and lowered the car-sized, 1-ton Curiosity rover
to its landing spot in 96-mile-wide (154-kilometer-wide) Gale Crater.
Then the platform flew off to its own crash landing, while Curiosity
sent out a text message basically saying, "I made it!"
That message was relayed by the orbiting Mars Odyssey satellite back
to Earth. A radio telescope in Australia picked up the message and sent
it here to NASA's Jet Propulsion Laboratory. When the blips of data
appeared on the screens at JPL's mission control, the room erupted in
cheers and hugs.
Because of the light-travel time between Mars and Earth, throngs of
scientists and engineers — along with millions who were monitoring the
action via television and the Internet — celebrated Curiosity's landing
14 minutes after it actually occurred.
Even the engineers who drew up the unprecedented plan for the landing
admitted that it looked crazy. But the plan actually worked.
Minutes after the news of the landing broke, commentator Allen Chen
brought more good news: "We have thumbnails!" Odyssey delivered pictures
showing the view from hazard avoidance cameras mounted on the rover.
Super Bowl pride
The touchdown marked a $2.5 billion triumph for what Doug
McCuistion, director of the Mars Exploration Program at NASA
Headquarters, called "the Super Bowl of planetary exploration."
Curiosity's primary mission is scheduled to last one full Martian year,
or almost two Earth years — but scientists hope the nuclear-powered
rover will keep going for years longer than that.
The successful landing sparked a swell of American pride for the
mission team as well as for NASA and the White House. The biggest
heart-swelling moment came during a post-landing news conference, when
the blue-shirted team behind Curiosity's entry, descent and landing
marched through the packed auditorium and high-fived their leaders.
"EDL! EDL!" the flag-waving troop chanted, but it might as well have been "USA! USA!"
President Barack Obama's science adviser, John Holdren, said that if
anyone had any doubts about American technological leadership, "there's a
one-ton, car-sized piece of American ingenuity, and it's sitting on the
surface of Mars right now, and it certainly should put any such doubts
to rest."
Obama himself issued a late-night statement via Twitter: "Tonight, on
planet Mars, the United States of America made history. I congratulate
and thank all the men and women of NASA who made this remarkable
accomplishment a reality."
NASA Administrator Charles Bolden said the successful landing marked a
significant step toward the Obama administration's vision of sending
astronauts to Mars and its moons in the 2030s. "The wheels of Curiosity
have begun to blaze the trail for human footprints on Mars," Bolden told
reporters.
Charles Elachi, director of the Jet Propulsion Laboratory, said
Sunday night's spectacle was a bargain, even at $2.5 billion. "This
movie cost you less than 7 bucks per American citizen," he said. Later,
John Grotzinger, the mission's project scientist, quipped, "That's a
movie I want to see."
Driving to a mountain
Curiosity is the biggest and most capable robotic laboratory ever sent to another celestial body: Its 10 scientific instruments are designed to study the chemistry of Mars' rocks, soil and atmosphere and determine whether the Red Planet had the right stuff to be habitable in ancient times.
The rover's prime target is a 3-mile-high (5-kilometer-high) mountain
inside the crater, known as Aeolis Mons or Mount Sharp. The mountain's
layers of rock could preserve billions of years' worth of geological
history, shedding light on the planet's transition from its warmer,
wetter past to its current cold, dry climate.
Some scientists think Curiosity could even detect the signs of present-day life, although NASA doesn't go that far.
Soon after the landing, engineers began activating the systems
onboard the rover. It could take weeks to get everything up and running
for the first drive. Grotzinger said the journey to Mount Sharp might
require one Earth year, because scientists want to take their time
studying Gale Crater's terrain. Pete Theisinger, the mission's project
manager, seconded the sentiment for going slow: "We have a priceless
asset, and we are not going to ... screw it up."
Theisinger recalled that he was on the job when NASA's Spirit and
Opportunity rovers landed on the Red Planet in 2004. "I never thought I
would ever say this, but this is better than that," he said. Spirit gave
up the ghost two years ago, but Opportunity is still at work on the rim
of a 14-mile-wide (23-kilometer-wide) crater called Endeavour.
Risky descent
The final phase of the Mars Science Laboratory's journey from Earth to Mars relied on technologies that had never been tried before in outer space — which is why it was called the "seven minutes of terror."
Seven minutes before landing, Mars Science Laboratory threw off its
cruise stage and began its plunge through the planet's atmosphere at a
speed of 13,200 mph (5,900 meters per second). It jettisoned two
solid-tungsten weights, shifting the spacecraft's balance to become more
like a wing. Small thrusters fired to put the craft through a series of
"S" turns to adjust the trajectory.
The heat shield weathered temperatures ranging up to 3,800 degrees
Fahrenheit (2,100 degrees Celsius). At an altitude of about 7 miles (11
kilometers), the spacecraft deployed its parachute, even while it was
traveling at supersonic speeds.
First the heat shield dropped away. Then the parachute and the back
shell flew off, leaving behind the rover and its rocket-powered "sky
crane."
The sky crane handled the final phase of the slowdown by firing eight
retro rockets. It descended to a height of about 65 feet (20 meters)
and lowered the rover to the surface on the end of three cables. When
the rover hit the ground, the cables were cut loose, and the sky crane
blasted itself away from the landing site.
Adam Steltzner, the engineer in charge of drawing up the landing
plan, said 79 explosive devices had to go off in just the right sequence
— otherwise, the landing would have almost certainly failed.
NASA went with the seemingly crazy system because the 1-ton Curiosity
is the heaviest payload ever delivered to the Martian surface. That
weight is too heavy for the airbag-cushioned system that was used for
previous Mars rovers, and too unstable to put on a lander with legs, Steltzner said.
Before the landing, Steltzner said he and his team were "rationally confident" and "emotionally terrified."
After the landing, he said Curiosity seemed to be in good condition
after an "extremely clean" descent. "It looks, at least to my eyeballs,
that we landed on a nice flat spot. Beautiful, really beautiful," he
said.
John Grunsfeld, NASA's associate administrator for science, said "the
'seven minutes of terror' has turned into the seven minutes of
triumph."
Running a relay
When Curiosity touched down, it was out of Earth's direct line of sight, so three orbiting probes — NASA's Mars Odyssey and Mars Reconnaissance Orbiter, as well as the European Space Agency's Mars Express — monitored the data being sent out by the spacecraft. However, only Odyssey was capable of relaying the data back immediately, using what's called a "bent pipe" communication mode.
The telemetry was picked up by a radio telescope in Canberra,
Australia, that's part of NASA's Deep Space Network, and relayed to the
Jet Propulsion Laboratory.
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