NASA/JPL/Cornell This 360-degree panoramic image of the Mars landing site in Gusev crater, released by NASA Jan. 12, was taken by two Cornell-developed cameras, or Pancams, on the rover Spirit. The image was processed by researchers in the Mars Lab at Cornell's Space Sciences building, then stitched together by Cornell astronomer Jim Bell's team at the Jet Propulsion Laboratory in Pasadena, Calif.

Cornell lands on Mars: Spirit 'hit the sweet spot'

Wally Skalij/Los Angeles Times Cornell astronomer Steven Squyres, center, principal science investigator for the rover missions, and NASA Administrator Sean O'Keefe, left, are jubilant at the Jet Propulsion Laboratory in Pasadena, Calif., as a signal is received from the Mars rover Spirit after its near perfect landing, Jan. 3.

By David Brand and Linda Grace-Kobas

PASADENA, Calif. -- In recent days, it seemed as if Cornell was everywhere in the solar system.

On Mars on Jan. 3, at 11:35 p.m. EST, the rover vehicle, Spirit, made a pinpoint landing on the planet, and only three hours later began returning its first low-definition, black-and-white pictures. "We hit the sweet spot," said a jubilant science-team leader, Cornell astronomer Steven Squyres.

On Earth two days later, high-definition color pictures of the landing site in the Gusev crater began flowing into the Jet Propulsion Lab (JPL) in Pasadena from the rover's panoramic cameras, or Pancams. The pictures, some of them in stereo, were color-corrected and balanced at the Mars Lab in the Space Sciences Building on the Cornell campus. They were described as "absolutely spectacular" by the leader of the Pancam team, Jim Bell, Cornell associate professor of astronomy.

Back on Mars, in the early hours of this morning (Jan. 15) the rover was scheduled to roll off its lander's west-northwest-facing ramp and onto the Martian surface to begin looking for clues in rocks and soils that Mars once had conditions, such as water, suitable to sustain life.

The bounce-down landing and the transmission of the clearest images ever taken of another planet were a huge success for NASA and a tribute to Squyres and his rover science team that over the next three months or so will send the golf cart-size rover on a voyage of exploration something less than a mile from the landing site in Gusev crater. The team also will guide a twin rover, Opportunity, scheduled to land on Mars Jan. 24.

The absolute star of the mission so far is Squyres, professor of astronomy at Cornell. He began the week with a flawless landing, with instruments behaving impeccably, and ended it by being named "Person of the Week" by the "ABC News/World News Tonight." (Read the story.)

"What a night," said an exultant Squyres Jan. 3 after an evening of mounting tension that broke only when mission controllers at mission manager JPL acquired the first signals that the rover had safely parachuted to the surface. Later, JPL officials said the parachute opened at 4.6 miles above the surface while the lander was traveling at 920 m.p.h., slowing the descent to 152 m.p.h. The retro rockets fired just 342 feet from the ground and the parachute bridle was released at about 27 feet. The airbags surrounding the lander made 28 bounces over 57 seconds, traveling at 33 feet a second.

The landing site, which by Jan. 13 had been pinpointed, is less than 330 yards from the first bounce, amazingly less than 10 kilometers (about 6 miles) from the center of the landing "ellipse," an imaginary runway in Gusev crater targeted by mission planners. The landing sequence took the spacecraft from 19,000 kilometers an hour (12,000 miles per hour) to a complete stop in just 6 minutes.

Spirit had traveled 487 million kilometers (302.6 million miles) to reach Mars since its launch from Cape Canaveral Air Force Station, Fla., on June 10, 2003. Its twin rover, Opportunity was launched on July 7, 2003, and is on course for a landing in Meridiani Planum, on the opposite side of the planet, on Jan. 25 at 5 minutes after midnight EST.

NASA chose Spirit's landing site based on evidence from Mars orbiters that the crater might have held a lake long ago. The crater is a basin the size of Connecticut created by an asteroid or comet impact.

After looking at the first Pancam images, Squyres said the pictures show a distribution of rocks that "are remarkably different from anything we have seen on Mars," with rock surfaces that are remarkably smooth. He speculated that the rocks have been broken up by a process akin to sand blasting, retaining the rocks' angularity but smoothing out their facets. He was unable to speculate about the composition of the rocks but noted that they have trails of debris behind them indicating that "we've landed in a fairly windy place." The site, he said, looks very much like a dry lake bed.

What seemed so incredible to many was the apparent trouble-free landing that left the Spirit lander standing upright on its base petal, allowing the deployment of the solar panels and the full charging of the rover's batteries. Last week the rover, which arrived on Mars crouched inside its curiously shaped lander, gradually unfolded so that on Jan. 11, Arthur Amador, a mission manager, was able to say that the status of the rover "is pretty darned perfect," with the vehicle standing on all six of its wheels. That night the rover's robotic arm, which carries three of five scientific instruments for examining rocks and soil, was released and locked into place for driving across the crater floor. And a day later, the rover's final lifeline to the lander, an umbilical cord for power and communications, was cut, leaving the rover as a fully functioning vehicle.

Actually getting it off the lander, though, has proved somewhat more complex than anticipated. Balky, deflated airbags, used for the bounce-down landing, failed to retract around the rover's south-facing forward ramp. Fearing that the rover's solar panels would brush against the airbag on the left side of the ramp during exit, mission engineers decided to turn the rover around to the ramp facing west-northwest. On Saturday night, Jan. 10, engineers carried out the operation on a full-scale model in JPL's "sandbox" testbed and determined that the rover would first have to be backed up 25 centimeters (about 10 inches) on the lander, then gradually swiveled around on its six wheels to the rear petal. This operation has been carried out gradually, and cautiously, this week.

Spirit is spending its first day on the surface about 9 feet from the center of the lander platform while its five scientific instruments are checked out. The rover will then drive a short distance, using instruments on its robotic arm to examine rocks and soil. A likely target of the rover, said Squyres, is a crater about 250 meters (800 feet) northeast of the landing site with a rim 200 meters (650 feet) in diameter. Squyres called the crater "an extremely attractive target" because it would "provide a window to subsurface Mars."

A less likely goal is a group of eastern hills shown in a panorama produced by Cornell's Mars Lab on Jan. 13 bathed in a deep, mystic red, that Squyres called "one of the most evocative images taken on this mission." The hills are situated about 2 to 3 kilometers (1 to 2 miles) away, possibly beyond the rover's range. But, Squyres said, "we will get as close to them as we can."

Said Squyres, "Spirit has shown us her new home, and it's a glorious place."

See the latest on the Mars mission at http://www.news.cornell.edu/releases/rover/rovermenu.html.