NASA loses contact with Mars orbiter

Tense mission controllers at JPL wait for the missing signal from Mars Climate Orbiter   MESSAGE BOARD Destination Mars  INTERACTIVE Destination Mars Pathfinder Visual Galaxy

September 23, 1999
Web posted at: 8:17 a.m. EDT (1217 GMT)

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By Robin Lloyd
CNN Interactive Senior Writer

(CNN) -- An engine fired to push NASA's next Mars mission into orbit around the red planet Thursday, but engineers failed to receive digital signals that all went well and have since lost contact with the spacecraft.

Following a 286-day journey, the Mars Climate Orbiter engine ignited as expected at 5:01 EDT. A signal was expected about 25 minutes later when the satellite cruised out from behind the planet, but engineers heard nothing.

"We're in a state where we're not quite sure what's happened," said Richard Cook, project manager for NASA's Mars Surveyor program, which includes Climate Orbiter.

"At this point, we're still very confident that we're in orbit in Mars and that we're going to see the spacecraft signal in a few hours."

Initial data showed some unexpected results, said project manager John McNamee. "The spacecraft was entering its corridor somewhat low," he said.

"The result of that could be an orbit that is significantly different than the one planned," he said. Engineers worked to recalculate the spacecraft's location so they could repoint gigantic radio antennae on Earth to receive signals from Climate Orbiter.

Project scientist Richard Zurek likened the effort of searching for the spacecraft to "looking for a signal in the cosmic haystack."

"Until we establish contact, we're really not going to have any idea of where the spacecraft was and how deep into the atmosphere it went," he said. An unplanned, steep entry into the atmosphere could have damaged Climate Orbiter.

Artist's rendering of the Mars Climate Orbiter

It also is possible that the engine firing caused the spacecraft to spin too fast for a signal to reach Earth.

Also, the spacecraft transmitter somehow could be turned off. Engineers discussed sending signals to turn it back on, said NASA spokesman David Seidel.

Engineers in the control room at NASA's Jet Propulsion Laboratory, shown on NASA-TV, were grim-faced as the minutes ticked by with no signal from Climate Orbiter.

Flight operations manager Sam Thurman alternated between staring at his monitor, staring at flight plans and pulling at his wedding band.

At 5:36 a.m., he looked at his watch and grimaced. Minutes later, engineers in the control room stood up and started making new plans.

Mars successes and failures

Mars Polar Lander

NASA and Russian/Soviet missions to Mars have had mixed results over the years, with NASA scoring loads of data in the 1970s with the Viking landers and in 1997 with the Mars Pathfinder's novel airbag landing, robotic rover and spectacular color images.

However, NASA's big-budget Mars Observer was lost just before it arrived at Mars in 1993. Mars '96, a Russian mission for which NASA also had high hopes, was destroyed during a launch accident.

The Thursday morning events were critical to NASA's first effort to look directly for water on Mars and study its weather closely, with the spacecraft set to enter the red planet's orbit to ready itself for contact with two upcoming lander missions.

Engineers avoided the worst case scenario -- no engine firing. That would have allowed Climate Orbiter to hurtle past Mars into space.

But losing contact with the spacecraft also will be a mission stopper if it isn't fixed.

However, a permanent loss of contact with Climate Orbiter would not stop the mission of its partner spacecraft -- Mars Polar Lander -- set to land on Mars on December 3, Zurek said.

Climate Orbiter's communications role for Polar Lander mission was to last up to 90 days.

Polar Lander was designed to extend a robotic arm to dig for water ice in the martian soil and conduct other science experiments focusing on martian weather.

Together, the missions cost $327.6 million and were aimed at understanding Mars' history and the potential for life in its past and elsewhere in the universe.

Climate Orbiter also was to relay signals for a follow-on Mars lander mission set for launch in 2001.

Between its communications duties, Climate Orbiter was to study Mars' weather on its own from a distance.

The orbiter carries a camera to track Mars' atmosphere and an infrared radiometer to measure the atmosphere's temperature, pressure and contents -- water vapor, dust, carbon dioxide.

Overall, the orbiter will study Mars' weather patterns for a martian year, equivalent to about two Earth years.