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Computer glitch blamed for European Mars lander crash

After trawling through mountains of data, the European Space Agency said Wednesday that while much of the mission went according to plan, a computer that measured the rotation of the lander hit a maximum reading, knocking other calculations off track.

That led the navigation system to think the lander was much lower than it was, causing its parachute and braking thrusters to be deployed prematurely.

"The erroneous information generated an estimated altitude that was negative—that is, below ground level," the ESA said in a statement.

"This in turn successively triggered a premature release of the parachute and the backshell (heat shield), a brief firing of the braking thrusters and finally activation of the on-ground systems as if Schiaparelli had already landed. In reality, the vehicle was still at an altitude of around 3.7 km."

Read more at: http://buff.ly/2gAJOSI
A tiny lander that crashed on Mars last month flew into the Red Planet at 540 kilometres (335 miles) per hour instead of gently gliding to a stop, after a computer misjudged its altitude, scientists said.
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11 comments
 
And the moral is, don't use a simple 2s complement integer variable to store vital numeric data.
 
I'm sure the only way that poor coder could possibly feel worse right now is if that was a manned lander. Thankfully it wasn't.
 
How did their testing regimen miss THAT??!
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