SPACE.com -- One More 'Silver Bullet' Left in Polar Lander Search


	One More 'Silver Bullet' Left in Polar Lander Search By Andrew Bridges and Andrew Chaikin posted: 08:51 am ET 06 December 1999

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PASADENA, Calif. - A sixth attempt to hear from the $165-million Mars Polar Lander was unsuccessful early Monday, leaving engineers with a final silver bullet to solve the problem, said Polar Lander Project Manager Richard Cook.

The latest attempt involved using the landers main antenna to scan the martian sky in search of the Earth. The antenna must be pointed within five degrees of Earth in order to make contact.

The silence left the Polar Lander team with one last best chance to raise the spacecraft, which has not been heard from since landing at 3:15 p.m. EST on Friday.

Early Tuesday morning EST there will be a second try at a relay link, when the orbiting Mars Global Surveyor uses the landers secondary, or UHF, antenna.

"Pretty much we are reaching the point where we have used up our silver bullets," Cook said.

The failure of previous attempts prior to Monday morning convinced the mission team that the lander had gone into a protective "safe" mode after it landed - if indeed it did land successfully.

Cook said the team would continue its efforts beyond Tuesday, although the odds of success diminish daily.

With each attempt to contact the lander and its companion Deep Space 2 microprobes, the likelihood grows that all three spacecraft failed.

On Sept. 23, the Mars Climate Orbiter - a $125-million satellite that was to have acted as a relay for the lander, but not the microprobes - was lost after a navigational error sent it too close to the planet as it entered the martian atmosphere.