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Comment by Cyph0n | Hacker News Reader

I really hope it's not a design issue, but that could definitely be the case. Why tin specifically?

Tin forms whiskers, small hairlike growths on the metal that can cause short circuits. We've already lost a satellite to this phenomenon, although I would hope it's not a problem anymore with current metallurgical techniques

https://en.wikipedia.org/wiki/Whisker_(metallurgy)

If I remember right, tin whiskers were determined to be the cause in the crazy Toyota runaway accelerator pedals a few years back. I think it's mainly an issue with lead-free solders, which RoHS has forced into widespread usage over the last decade.

It was hypothesized, but not accepted as a cause: http://www.autonews.com/article/20120727/OEM11/120729908/nht...

The problem was ultimately found to be a combination of pedals being pressed by floor mats, pedals sticking on their own, and drivers pressing the wrong pedal.

ESA is not part of the EU -- it's an international organization, and is exempt from national law in the same way as an embassy. Even if RoHS applies to spacecraft, it probably doesn't apply to ESA's spacecraft.

That's not to say acquiring non-RoHS components isn't made more difficult by RoHS.

RoHS does not apply to spacecraft. In fact, companies specialize in things like replacing RoHS solder balls on BGA parts with lead solder ones.

Some some comments on the military in Aerospace issues with RoHS - with photos:

http://www.militaryaerospace.com/articles/print/volume-20/is...

https://en.m.wikipedia.org/wiki/Tin_pest

Just in case, the NASA page dedicated to the matter:

https://nepp.nasa.gov/whisker/index.html

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