Do you all remember the infamous crash of the Mars Climate Orbiter? It was one of two NASA missions to the Red Planet that crashed in 1999 as they reached the end of their long journeys from Earth. Mars Polar Lander made a hole in the rusty dirt in in December – after an on board sensor designed to extinguish the rocket motor once it landed mistook the jolt of the landing gear deploying as a safe touchdown – and shut off the engine while MPL was still 1200 feet above the surface.
MCO was supposed to orbit the Red Planet – but instead entered the atmosphere way too low and burned up in September . The navigation error occurred because the NASA team at the Jet Propulsion Lab in La Canada, CA was using the metric system (newtons) to measure the force created by a thruster – while the Lockheed Martin team in Denver was using imperial units (pound force). One pound force equals approximately 4.45 newtons, and the thruster firings were nothing more than mouse farts, so the discrepency was not obvious just by looking at the numbers. Unfortunately, the two teams never cross-checked their navigantion data. The rest is history – and the ignominous end to then NASA Administrator Dan Goldin’s “Faster, Better, Cheaper” approach to space exploration.
Which brings me to the posting below on NASAWatch.com. NASA is under a mandate to go metric because of the MCO mishap. But the agency is resisting the change for some reason. The irony is it was the JPL/NASA team using the metric system in the first place. LockMart was using pounds.
These days there is a lot of talk about the US remaining competitive in a global economy – and switching to the metric system is something that we should have done a long time ago. Jimmy Carter tried in the 70s…but he apparently didn’t have the newtons to move the masses.
“Following the loss of the Mars Climate Observer, the NASA Office of Inspector General initiated a review of the Agency’s use of the metric system. By law and policy, the metric system is the preferred system of measurement within NASA. However, our review found that use of the metric system is inconsistent across the Agency. A waiver system, which was required by law and put into effect to track metric usage and encourage conversion, is no longer in use. In addition, NASA employees are given little guidance on the Agency’s policy and procedures regarding use of the metric system.”