Mars Lander: Lost, Not Forgotten

Engineers have another opportunity this week to contact NASA's Mars Polar Lander, nearly two months after the $165 million craft disappeared descending to the planet's surface.

The latest attempt to receive a signal from the lost probe failed Monday, but antennas around the world will turn their electric ears to the Red Planet again Friday in hopes of hearing a reply, space agency officials said.

The search was renewed after Stanford University scientists said their antenna might have picked up a signal from the lander in December and January. The signals were so weak that nobody noticed until a review of recorded data several weeks later.

NASA officially ended its search on Jan. 17, but new commands ordering the spacecraft to reset its internal clock and signal Earth were beamed at Mars last week.

However, data collected in the days that followed contained no signals that could have been sent by the lander.

Stanford scientists will continue to analyze the information collected and a signal could still be detected.

Officials from NASA's Jet Propulsion Laboratory have accepted offers from those who operate 14 antennas measuring 82 feet each at Westerbork in The Netherlands, a 250-foot antenna at Jodrell Bank near Manchester, England and at another set of antennas near Bologna, Italy.

"The international community has shown a real interest in being involved in our search," said Richard Cook, the lander's project manager at JPL. "We appreciate their efforts and I think it shows that Mars is something that captivates everyone's imagination."

The latest commands sent to the spacecraft continue to order it -
if it can hear anything - to reset its internal clock and send a signal to Earth.

The European antennas and possibly the 150-foot Stanford antenna will be listening for the reply on Friday. It takes about 16 minutes for a signal to travel between Earth and Mars, which are currently separated by about 181 million miles.

The probe was last heard from Dec. 3 as it was about to enter the Martian atmosphere for a 90-day mission to study the planet's climate and dig for frozen water beneath the surface. It was the second NASA spacecraft to disappear in three months.