June 19, 2008
Data Glitch Forces Phoenix to Lose Day of Work
NASA engineers worked Wednesday to fix a glitch that caused the Phoenix lander to lose a day's worth of data during its mission near Mars' north pole.
Engineers discovered the problem Tuesday evening when Phoenix sent a single piece of data 45,000 times. The Phoenix lander had been digging a trench inside a polygon-shaped surface feature, likely caused by seasonal changes and ice shrinkage.
The spacecraft attempted to send back pictures of the trench, but the data overload stopped the lander from saving photos of the atmosphere and landscape. Now scientists plan to transmit information to Earth through two orbiters, rather than store the data overnight.
Scientists back on earth maintain the lost photos weren't crucial.
Mission scientist Ray Arvidson of Washington University in St. Louis said, "It's unfortunate to lose any bit of science, but it's not really critical stuff that you kick yourself over."
The lander, on a $420 million mission, would store the day's work in its flash memory, but the duplicated data caused the spacecraft to power down without saving anything.
"We're rather annoyed," said project manager Barry Goldstein of NASA's Jet Propulsion Laboratory.
Engineers worked around the glitch, although its cause remains unknown.
However, NASA delayed Wednesday's digging to not further stress Phoenix's memory.
This is not the first time the lander has experienced problems.
The data glitch is the third delay since May 25th when Phoenix landed in the Martian artic. During the three-month mission other malfunctions were attributed to relay problems with orbiting Mars probes, through which Phoenix transmits information to Earth.
Scientists contend Phoenix will find white material-possibly ice or salt-when it digs in a foot long trench on Thursday. The lander had not found the white material present in trenches before the data glitch.
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