You know all the rumors about how Americans are absurdly goddamn stubborn about not switching to the metric system? The rumors are true, and we wouldn’t even switch after a unit conversion issue caused us to lose a hundred million dollar spacecraft to the cosmic fucking wind.
Today’s Moment of Science… the loss of the Mars Climate Orbiter.
The 1990s were a relatively lean time for NASA. We sent the Mars Observer out to the red planet, only to have it ghost on us mere days before orbital insertion. All communication with the craft was lost and we technically still don’t know where in sweet Andromeda’s ass it landed. With an expensive failure on our hands, the government asked NASA “got anything way less ambitious that still has ‘Mars’ in the name?”
Launched on December 11, 1998, the Mars Climate Orbiter was planned to be the first interplanetary weather satellite. It was designed to gather data on Mars’ climate, serving as a relay station for data from the Mars Polar Lander, which was launched shortly after the orbiter.
While the craft was making its way to Mars, the trajectory was monitored and thrusters were adjusted as needed to keep it on course. NASA worked with Lockheed Martin to construct the spacecraft, and for some reason, a piece of Lockheed Martin’s software for the project did its calculations in imperial. NASA did their calculations in metric.
If you send your data in pounds to software that incorrectly assumes you’re using newtons, you’re gonna have a bad time. One pound is about 4.45 newtons. I’m not a mathematician but that works out to being, give or take, entirely fucked.
They were aiming to be about 200km above the surface of the planet for the attempt to drop the vessel into orbit, but from all those adjustments they’d made just a tad incorrectly, they were coming in low, on a trajectory to swing within 57km of the planet’s surface.
On September 23, 1999, when the team that planned and worked on this mission should have been celebrating? Instead they were left with less than nothing. The Polar Lander was lost as well just two months later. Perhaps the spacecraft burned up upon entering the Martian atmosphere. Maybe it survived and it’s still wandering around, lost in space. The craft that represented countless hours of work was just gone forever because of an infuriatingly small error.
NASA never played the blame game for the discrepancy. A rep for NASA said “I think the problem was that our systems designed to recognize and correct human error failed us. This was not a failure of Lockheed Martin. It was systematic failure to recognize and correct an error that should have been caught.”
It’s unclear if there’s ever been a bigger boner due to a problem with unit conversion, but if losing a hundred million dollar spacecraft isn’t enough to drag the US on board with the metric system? Seems we’re stuck with feet, ounces, gallons, and whatever stones are.
This has been your daily Moment of Science, grateful for my high school chemistry teacher’s advice: “without units, your answer is wrong.”
To get the daily Moment of Science delivered straight to your inbox and be entered for a giant giveaway next month (my birthday means gifts for you), head to patreon.com/scibabe.
I had a prof in College (back in the late 90’s) who did a lot of work for NASA, and other assorted and sundry aerospace companies, and he would swear up and done that English units were perfectly fine, and so easy to convert between and use, once you memorized every little conversion factor and relationship.
At first, we thought he was joking, they we realized he was dead serious.
The loss of the Climate Observer wasn’t a surprise to any of his students.
PS He didn’t do any work on that project.
The Gimli Glider was another (but less catastrophic) fuck up caused by similarly stoopid thinking.