In September 1999, NASA's $125 million Mars Climate Orbiter was completely lost as it headed into a lower than planned orbit. What was the cause of this mistake?

serpa

"The 'root cause' of the loss of the spacecraft was the failed translation of English units into metric units in a segment of ground-based, navigation-related mission software, as NASA has previously announced," said Arthur Stephenson, chairman of the Mars Climate Orbiter Mission Failure Investigation Board. "The failure review board has identified other significant factors that allowed this error to be born, and then let it linger and propagate to the point where it resulted in a major error in our understanding of the spacecraft's path as it approached Mars. http://mars.jpl.nasa.gov/msp98/news/mco991110.html Jun 09 11, 1:35 PM