The Curiosity rover streaked through the thin Martian atmosphere Sunday night to a safe and stunningly smooth night landing on a faraway flood plain, ready to launch the most sustained human study of our closest planetary cousin.
Shouts of joy and relief went up from relieved controllers at NASA's Jet Propulsion Laboratory in Pasadena as a signal arrived at mission control at 10:32 p.m. PDT, confirming that the Mars Science Laboratory (MSL) spacecraft that carried Curiosity had survived a perilous descent and landed intact.
"Wow. It was picture perfect. It almost seemed dreamlike," said NASA Ames geologist David Blake of Los Altos, creator of a $40 million tool on Curiosity that will do extensive soil analysis of the planet, critical to understanding the possibility of Martian life, past or present.
As the rays of a late afternoon sun illuminated the frigid Martian landing site, elated and slightly amazed mission controllers reported that the one-ton nuclear-powered spacecraft had completed all its automated landing tasks - surviving a frightening entry through the planet's thin atmosphere, dubbed "Seven Minutes of Terror."
Confirming its arrival, it sent home a grainy snapshot of itself - a 64 by 64 thumbnail pixel image of its own shadow.
"The Seven Minutes of Terror has turned into the Seven Minutes of Triumph," said NASA Associate Administrator for Science John Grunsfeld.
In Mountain View, more 6,000 thrilled Earthlings
The crowd leaped to its feet at the good news. Several giddy groups of friends joined in celebratory dancing.
Overhead, above the western horizon, the planet twinkled in an inky sky.
The odds of landing safely on Mars were only about 40 percent, based on all missions by all countries, according to NASA.
The deceleration of MSL's descent has been compared to driving from 65 miles per hour to zero - in only 2.1 seconds.
This specific mission, costing $2.5 billion, was the hardest NASA has ever attempted in the history of robotic planetary exploration. The size of a Mini Cooper, it had no protective cushions and raced through Mars' thin atmosphere like a shooting star.
The MSL spacecraft that carried Curiosity succeeded in every step of the most complex landing ever attempted on Mars, including the final severing of the bridle cords and flyaway maneuver of the rocket backpack.
Its first grainy photo was followed by a second, larger 250 pixel image. The initial set of images will come from the one-megapixel "Hazard-Avoidance" cameras attached to the body of the rover, to prevent it from striking rocks or falling into canyons. Once engineers have determined that it is safe to deploy the rover's higher-tech cameras, a process that may take several days, Curiosity will begin to survey its exotic surroundings. Eventually, panoramic color shots will be assembled.
"The first thing we saw were rocks and a wheel. Everybody just erupted," said Blake.
Adam Steltzner, the leader of the JPL team that dreamed up a new way to approach the planet, called the landing "extremely clean."
"We touched down in conditions that were on the more benign side of our expectations," said Steltzner, a graduate of Mill Valley's Tamalpais High School and UC-Davis. "Our navigation error was on the low side of our expectations. There was good alignment between celestial sensors. And our powered flight appears to have been excellent. We landed with 140 kilograms of fuel reserves out of 400 kilos carried in."
"That great things take many people working together, to make them happen, is one of the fantastic things of human existence," said a teary-eyed Steltzner. "In my life...this is, and will forever be, the greatest thing I have ever been given."
Because a Martian satellite was transmitting telemetry in real time - the scientists could watch MSL's speed, mileage and other metrics on a panel, just like a dashboard on a car. Briefly,
The success of each step was announced with a specific tone, converted to data on JPL computers.
Its descent riveted the global audience. NASA's website got so much traffic that it shut down.
"It is a once in a lifetime experience," said Miriam Glazer of Mountain View, bundled up in blankets, who arrived at 5 p.m. to reserve her seat.
While Curiosity is not equipped specifically to seek life, the unifying theme of the mission is the study of the planet's geology and chemical compounds, which contains clues essential to any life that may exist there, now or in the past.
"Today, the wheels of Curiosity have begun to blaze the trail for human footprints on Mars," said NASA Administrator Charles Bolden.
"It will seek to answer age-old questions about whether life ever existed on Mars," he said, "or if the planet can sustain life in the future.—