However, one Polar Lander team member contradicted the report, telling SPACE.com that the cause of the lander's demise was still unidentified. The scenario described by spacedaily.com is only "one of many things that may have done in the lander," said the team member.

The news report blames a special switch, called the contact switch, which was designed to turn off the lander's three braking engines just before touchdown. The engines were to slow the spacecraft during the final 40 seconds of its descent to the surface of Mars.

Speaking to SPACE.com, a project engineer confirmed that there is some concern that the contact switch might have been triggered prematurely. But the engineer denied that it had been identified as the culprit. "There's far, far less than a smoking gun there," said the engineer.

The so-called contact switch was to trigger a "flag," or marker, in the lander's onboard software when any of the three landing legs touched the martian surface. This in turn would be noticed by the computer, which would turn off the lander's engines.

However, according to the report, the contact switch could have been triggered inadvertently when the spacecraft's landing legs were deployed, about 90 seconds before landing. The force of deployment, said spacedaily.com's source, could have caused the legs to flex enough to trigger the switch. The story said several simulations conducted by the Polar Lander review board suggested this.

About 20 seconds before touchdown, while the craft was still 164 feet (50 meters) above the surface, the lander's computer was to begin looking for the software flag signaling that the contact switch had been triggered. At that point, if the flag had already been set, the computer would wrongly conclude that the spacecraft had already touched down. It would have then turned off the engines, and the lander would have fallen to the surface, impacting at a speed of 134 miles per hour (60 meters per second).

According to the spacedaily.com report, the flaw went unnoticed in pre-flight testing. One team tested the deployment mechanisms for the landing legs, said the report, while a different team evaluated the lander's performance during its final descent. The second team re-set the lander's computer, the report said, erasing the prematurely set software flag. Thus, the problem was never discovered.

(A JPL engineer told SPACE.com that the problem, if real, could easily have been avoided with a minor change in computer software.)

Richard Cook, the Polar Landers project manager, said Wednesday that the review panel investigating the spacecrafts loss was looking at issues related to the landers legs, but did not know anything further.

John Casani, chairman of the internal review board at NASAs Jet Propulsion Laboratory, declined to comment.

NASA Administrator Daniel Goldin was asked about the failures of the Mars Polar Lander and Mars Climate Orbiter at a congressional subcommittee hearing on Wednesday but declined to answer. He said any of his viewpoints about what went wrong could unfairly influence a 17-member investigation panel headed by former Lockheed executive Thomas Young. That panel is due to report its findings to Goldin on March 15.

"The results are going to be very, very important," Goldin told Congress. "But I don't want to bias what Thomas Young and 16 other experts can come up with."

He did say, though, that "I think we have to take a hard look" at how best to explore Mars.

In other news, JPL officials announced Wednesday that they would likely cease attempting to listen for faint signals from the errant Polar Lander.

Scientists at Stanford University had thought they had detected faint signals from the lander on December 18 and January 4, but said Tuesday that further analysis had proved them wrong.

"Basically, the signal is too good is the short answer," Cook said. "When you have a signal propagating across 1.6 AUs (one AU, or astronomical unit, is the distance from the Earth to the sun, or 93 million miles), from Mars to the Earth, you'd see it spread over the spectrum. That wasn't the case here."

The Stanford claims had sparked an international scramble to contact the lander. Cook said that was unlikely to resume.

"I don't know if we are ready to say definitively, but it seems doubtful," Cook said.

NASA may still use the Arecibo Observatory's mammoth dish to listen a last time later this month.