[meteorite-list] NASA's Rover Touches Down Safely on Mars

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Thu Apr 22 10:31:57 2004
Message-ID: <200401041023.CAA20616_at_zagami.jpl.nasa.gov>

http://www.latimes.com/news/science/la-sci-mars4jan04,1,7206708.story

NASA's Rover Touches Down Safely on Mars

Against the odds, Spirit probe lands upright, allowing immediate
communications. It will look for signs that water once was on the planet.

By Thomas H. Maugh II and Charles Piller
Los Angeles Times
January 4, 2004

NASA's Spirit rover survived its fiery plunge through the thin
Martian atmosphere Saturday evening, bouncing across the
planet's red landscape to a jarring but safe landing at Gusev
Crater. Within hours, the rover began transmitting its first images
of Mars, a series of stunning views of the area around the lander.

The high-definition camera provided a series of panoramic views
of the crater, showing rocks and terrain in astounding clarity. One
dramatic photo showed a boulder scant yards from the lander,
indicating how close it had come to disaster. Another showed a
panoramic scan of the area surrounding Spirit.

The first data package also included lower-quality pictures taken
by the descent camera as the rover neared the surface.

The images capped a day of celebration for NASA and the Jet
Propulsion Laboratory in Pasadena, which designed and built the
rover.

Cheers and clapping had erupted in the JPL control room earlier as
mission control announced that NASA's Goldstone antenna in the
Mojave Desert had acquired "a very strong signal from the rover's
low-gain antenna" at 8:51 p.m.

Scientists and engineers in the control room who had been visibly
tense during the craft's descent hugged one another and shook
hands all around as it became clear that Spirit had made a
near-perfect landing.

"This is a big night for NASA," said NASA Administrator Sean
O'Keefe shortly after the landing. "We're back. I'm very, very
proud of this team that we are on Mars." He then poured
champagne for the team leaders.

The safe arrival, the first since NASA's Mars Pathfinder reached
the Red Planet on July 4, 1997, marks a major step forward in
NASA's search for signs of life on Earth's closest neighbor.

Spirit will spend at least the next three months searching for
evidence that water once was common on the surface of Mars, a
prerequisite for the existence of life.

Launched on June 10 from Cape Canaveral, Fla., the craft traveled
more than 300 million miles for its historic rendezvous.

Against the odds, Spirit landed in an upright position, allowing
immediate communications with Earth.

"We've got many more steps to go before this mission is
completely over, but we've retired a lot of risk at this time," said
Peter Theisinger, the rover project manager.

Two minutes after the signal was acquired, the 384-pound lander
began collapsing its air bag so that it could unfold the petals of its
pyramid-shaped capsule and begin deploying its solar panels to
recharge its batteries.

After raising its camera and antenna mast, Spirit transmitted its
first batch of data and pictures to the Mars Odyssey orbiter as it
passed over the landing site about 11 p.m. Odyssey relayed them
to Earth a few minutes later.

The team got its first hint of impending success at 8:35 p.m., when
Goldstone received a brief signal that the rover was bouncing
across the surface, indicating that the craft had made it through the
most difficult phase of the descent.

But the team immediately lost the signal as the rover's small
antenna gyrated wildly while the craft rolled to a stop.

Controllers waited anxiously for several tense minutes until the
signal was reacquired.

When the signal finally came, all the worries of the last four years
of work seemed to evaporate in a puff of elation.

"This is the most important first step.... We've done very well," said
JPL's Matt Golombek, laughing for joy. "We're happy folk."

Spirit will spend the next nine days checking out its internal systems,
charging its batteries, and photographing the site before it finally rolls
off its landing platform and begins its geological work.

Spirit is the most ambitious effort yet to roam the surface of another
planet. It is part of a small fleet of spacecraft sent toward Mars in an
effort to answer one of the most captivating questions in science: Has there
been life on other planets?

Spirit and its twin, Opportunity, are the most sophisticated of the
spacecraft, and hopes are high that they will provide a bounty of information.

The stakes were even higher because NASA's last two Mars missions, the Mars
Climate Orbiter and the Mars Polar Lander, failed in 1999. A third mission
planned for 2001 was canceled when outside reviewers concluded the agency
was attempting too much with too few resources.

The two new missions, costing $820 million together, have consumed the
energy of hundreds of scientists and engineers for the last four years and
destroyed the recent holidays for mission controllers.

Reporters were camped out in JPL's newsroom waiting for the fateful moment
of arrival and hundreds of thousands of people were watching on the Internet.

Earlier Saturday, the JPL campus exuded more excitement than anxiety as four
years of intensive efforts were perched on the knife edge between success
and disaster.

Small knots of employees joked and talked in the bright sunshine of the lab's
central campus; even top mission managers seemed upbeat and relaxed.

That almost preternatural sense of calm was described by JPL Director Charles
Elachi as essential to the mission's success.

"We are nervous," he said. "But when you feel you have done your best,
you've done everything possible, then it's important to be calm - because
there may be decisions and judgments to make."

All the years of preparation paid off.

A planned last-minute course correction proved unnecessary because the craft
was already on a "bull's-eye" course for its targeted landing site in Gusev
Crater.

"This is essentially perfect navigation," said JPL's navigation team chief,
Louis D'Amario. "We couldn't possibly have hoped to do better than this."

But the team did have to make some last-minute adjustments in the landing
program to take into account a dust storm on the opposite side of Mars.

Because dust absorbs more sunlight than the planet's surface, Mars' upper
atmosphere was about 10% to 15% warmer and thinner than normal, said
mission manager Mark Adler.

The lander's parachute was therefore reprogrammed to open 13 or 14 seconds
earlier than originally planned to ensure that the craft didn't crash into
the surface, he said.

JPL's scientists and engineers were confident that they had done everything
they could to prepare for Spirit's landing - a harrowing maneuver that
Theisinger described as the riskiest part of the mission.

Mission controllers call the entry "six minutes from hell" because the
spacecraft's speed had to be reduced from 12,000 mph to effectively zero.
The craft relied on a parachute and retrorockets to slow its descent before
bouncing to a halt on its cocoon of air bags.

The whole process had to be handled autonomously by Spirit's on-board computer.
Earthbound controllers could only sit back and watch. And worry.

"It was six minutes from hell, but in this case we said the right prayers and
we got up to heaven," said Ed Weiler, NASA's associate administrator for space
science.

Spirit's successful landing gives a boost to the spirits of planetary scientists,
who have recently witnessed more failures than successes with Mars missions.

Last month, Japan conceded that its Nozomi orbiter had failed because of
navigational and equipment problems. Its mission was aborted.

The fate of Britain's Beagle 2 lander, carried to Mars aboard the European
Space Agency's Mars Express orbiter, is still in doubt.

Beagle 2 was scheduled to land in the Isidis Planitia basin late Christmas Eve
Pacific time, but controllers have not been able to make contact with the craft
and many fear it is lost.

Mars Express did go into orbit, however, and controllers have been altering its
path so that it can attempt to make contact with Beagle. They are scheduled to
begin those efforts today.

NASA's two rovers, Spirit and Opportunity, were launched last year to take
advantage of Mars' closest approach to Earth in 60,000 years, a celestial
alignment that brought it within 35 million miles of Earth.

The armada marks the beginning of humanity's strongest effort yet to determine
whether life has ever existed on Mars.
Received on Sun 04 Jan 2004 05:23:56 AM PST