The Mars Climate Orbiter was undergoing "aerobraking" to take it into orbit around the Red Planet when the National Aeronautics and Space Administration (Nasa) in California lost radio links. Scientists at Nasa's Jet Propulsion Laboratory in Pasadena said contact was broken when the orbiter went behind Mars yesterday morning but they were hoping to be able to regain radio links during the satellite's subsequent orbits.
John McNamee, Mars Surveyor project manager, said the craft may have entered orbit on a different track than the one predicted by scientists. They were attempting to locate its course.
The orbiter's main engine fired for 16 minutes to slow down the spacecraft from its interplanetary speed of 12,300mph to its orbiting velocity of 9,840mph. It was part of a manoeuvre designed to send the spacecraft into a large elliptical orbit and so avoid crashing into the planet's surface or missing the orbital path completely and being sent into deep space.
"We know we had a functioning spacecraft going into the Mars orbit-insertion burn. We know the burn started on time. We saw five minutes of it before it went behind the planet, but from that point on we've had no contact from the spacecraft," Dr McNamee said.
One theory is that the orbiter, launched in December, may have entered its orbital corridor at a lower than expected angle. "The result of that could be an orbit that is significantly different than the one planned and we may have our navigation predictions at the tracking station incorrect," Dr McNamee said. Nasa tried to update its predictions yesterday to see if it could track the spacecraft's correct position using radio signals that take 11 minutes to travel the 122 million miles between Mars and Earth.
However, Dr McNamee said that, based on the latest navigation results, the spacecraft was entering its corridor somewhat low. "The result of that could be an orbit that is significantly different than the one planned and we may have our navigation predictions at the tracking station incorrect," he said.
The Mars Climate Orbiter's science mission will last about two years, during which time it will provide detailed information about the planet's atmospheric temperature, dust, water vapour and clouds.
Nasa hopes to gather data on the atmospheric conditions on Mars through each of its seasons, and learn about past and future weather.Reuse content