Earth Changes TV - NASA Checking Possibility That Mars Lander Sent Signal To Earth

NASA Checking Possibility That Mars Lander Sent Signal To Earth...01/26/00

PASADENA, California (CNN) -- Mission managers at NASA's Jet Propulsion Laboratory say the Mars Polar Lander may have tried to phone home after all -- on a bad connection -- and they sent new commands to the lander Tuesday in another attempt to achieve contact with the presumed lost mission.

The commands, sent Tuesday, will instruct the lander to send a signal directly to Earth to an antenna at Stanford University.

Similar attempts using the Stanford antenna were conducted in December and earlier this month, but no signal was immediately detected. Now, the Stanford team says additional processing of the data shows a weak signal, possibly from Mars, was received during those attempts. This week's test will seek to replicate those results.

Even if the signal came from the Polar Lander it would not mean the mission could be saved. The signal is extremely weak, indicating a failure in the lander's primary transmitter. It is unlikely that problem could be corrected or that science data could be returned. However, it would give the team a few more clues in determining how the mission failed.

The Stanford receiving station will listen Wednesday to see if it detects any signal from the lander. Results from the test are not expected for several days.