Mars rover in 'critical' condition

3.00pm


PASADENA - NASA engineers today declared the crippled martian rover Spirit to be in "critical" condition and said the vehicle would likely remain idle for several days, even weeks.

Meanwhile, the scientists geared up for the landing of a second robotic explorer, Opportunity, on Mars this weekend on the other side of the planet from the troubled Spirit.

Spirit, which had operated virtually problem free for its first 18 days on the red planet, has been out of commission since an abrupt, unexplained communications breakdown on Wednesday, less than a week after successfully rolling off its landing platform to begin searching for geologic signs of life-sustaining water.

Two brief transmissions received from the six-wheeled craft early on Friday consisted mostly of error messages and limited engineering data, said mission controllers at the Jet Propulsion Laboratory who manage the Mars project for NASA.

For now, NASA engineers and scientists will be playing a sort of interplanetary game of 20 questions with the rover, as they attempt to send commands to the vehicle and gradually tease out electronic clues to what ails it.

"We will not be restoring functionality to Spirit for a substantial period of time, several days, maybe weeks, from what we can see today," Mars Exploration Rover Project Manager Pete Theisinger told reporters at a JPL briefing.

He described the rover's condition as "critical," adding, "We do not know to what extent we can restore functionality to the system because we don't know what's broke.... We have a long way to go with the patient in intensive care."

Theisinger said that while the mission's flight software was malfunctioning -- plunging the rover into a continual "processor reset loop" -- he suspected that the root cause of the problem was some kind of hardware issue, such as a mechanical glitch or sensor flaw.

The problems began when the craft failed to finish carrying out a sequence of instructions to manipulate an instrument on the craft called the mini-thermal emission spectrometer, or "mini-TES," which is used to measure the infrared emissions given off by rocks and soil to determine their mineral composition.

"We were doing a motor operation that did not run to completion when this thing started," he said. Spirit has been unable to return any science data, pictures or telemetry information since early Wednesday.

The good news, Theisinger said, was that Spirit was now sending some limited data back to Earth, giving engineers something to go on as they puzzle through the difficulty.

He said he viewed the chances of restoring Spirit to perfect working order as "low," but likewise said it was unlikely that the rover would remain completely incapacitated.

Theisinger also said he thought that whatever the problem turned out to be, it was probably a "one-off" malfunction that should not necessarily stymie Spirit's identical twin, Opportunity, once it arrives.

JPL project managers said they were moving ahead as scheduled with plans for Opportunity, which is due to land late on Saturday night on the opposite side of Mars in a region called the Meridiani Planum, a smooth plain near Mars' equator.

In that region, NASA scientists have detected an abundance of gray hematite, a mineral that on Earth usually forms in association with liquid water.

Earlier today, the European Space Agency said its Mars mission had confirmed the presence of frozen water on the planet's surface.

- REUTERS