[jaak]

I'm not an expert on this, but there's a famous case from 1998 where the Galaxy IV telecommunications satellite developed "tin whiskers" on it's soldered connections which caused an electrical short resulting in a total loss.

So, at least in this case solder was used on a satellite.

https://en.wikipedia.org/wiki/Galaxy_IV

[thewonderidiot]

Solder is used extensively in satellites nowadays. The catch, though, is that you must use leaded solder, because the lead dramatically decreases the occurrence of tin whiskers. RoHS has been rather annoying in the aerospace industry, because anything RoHS compliant can't safely fly.

[varjag]

Weren't a lot components RoHS-compliant intrinsically anyway, without any change in process whatsoever?