Mars-probe failure 'human error'

From BBC website on 14 April 2007

The US space agency, Nasa, has said that human error was to blame for the failure of the $247m (£124m) Mars Global Surveyor spacecraft (MGS). The craft was 10 years old, but changes made to the computer software caused batteries to overheat and fail 5 months later.

Also, in an article by Staff writers on 17 April 2007 from itnew.com.au

It has been determined that someone uploading commands to update positioning in the High Gain Antenna's positioning for contingency operations wrote the information to the wrong memory address in the onboard computer.

"This resulted in the corruption of two independent parameters and had dire consequences for the spacecraft," the report released by NASA explained.

The corrupted upload happened, according to the report, because two previous updates conflicted and programmers were trying to fix the discrepancy.

NASA said the error caused problems with a solar array, which caused the craft to go into contingency mode, exposing batteries to direct sunlight and overheating. That ultimately depleted the batteries, most likely within 12 hours, according to the report. A second parameter error caused the antenna to rotate away from Earth, which blocked communications.

NASA said that more thorough operating procedures and processes and periodic reviews could have reduced the chance of errors.

Andy Brazier