On September 23, 1999, after nine months of travel through the empty void of space, NASA’s Mars Climate Orbiter began its descent into orbit around the red planet… but something was wrong. The probe’s trajectory was too steep, bringing it far too close to the surface. The agency lost contact with the probe four minutes after the maneuver began, and the 193 million dollar spacecraft disintegrated in the atmosphere shortly afterwards.
Lockheed Martin, the primary contractor for the project, was no stranger to this kind of complex engineering project. NASA had decades of experience in space exploration. Both organizations are staffed by some of the best and brightest people in their fields. So what could have caused this?
According to NASA’s investigation into the failure, it was a basic misunderstanding. Lockheed Martin had written some trajectory code using English engineering units. NASA wrote their software in metric. The mismatch skewed the calculations, and the result threw the probe off course just enough for it to plummet into Mars instead of circling around it.
One particular aspect of the problem stands out here: the lack of communication between the contractor and their client. A simple question from either side could have identified this problem, but communication channels between the two were poor and the results speak for themselves.
That might sound almost absurd, but this is exceptionally common in the tech industry. One of the main frustrations that many engineers face is frequent changes in requirements, and a fair number of those come from unspoken assumptions and unasked questions. Just spending a week or to make sure that everyone is on the same page can save a project from months of extra work, or even from outright failure
When you work with someone, talk with them often. If you ever have any doubts about what they want or you think there’s any chance of a misunderstanding, even if it seems silly or stupid to you, ask for a clear explanation. There’s always a chance that you’ll be seen as uninformed for asking so many questions about such basic things, but compared to a 193 million dollar space probe that’s a pretty small price to pay.
Sebastian Whalen, Software Developer Missing Link Technologies ltd.