ABSTRACT
Poor informative and explanatory skills are costly. In 1999, failure to communicate the difference betweenpounds and newtons cost NASA’s Jet Propulsion Laboratory ( JPL) the $125 million Mars Climate Orbiter mission. When the spacecraft was entering the Martian atmosphere, Lockheed Martin engineers sent the orbiter’s final navigation information to JPL in Pasadena using the English measurement “pounds” of force. But JPL had programmed its computers to calculate orbital navigation parameters and thruster firings using the metric “newtons” of force. The JPL group assumed the spacecraft’s orbiting instructions had been calculated using the metric system. Neither group saw this problem, and inaccurate trajectory commands were sent to the spacecraft.
