[ale] [OT] grounding in space

[agcarver+ale at acarver.net (Alex Carver)]

On 2017-08-28 10:50, Jim Kinney wrote:
> The (bs) EMP bags made me think (usually a good thing!) about circuit design (a 
> field I'm not good in).
> 
> For a spacecraft, the obvious choice for ground plane is the craft framework 
> itself. Relative to the typical power loads in the various modules on ISS, the 
> frame is a "near infinite supply or sink of electrons".
> 
> But space weather is nasty. Solar flares are huge problems. How is a system 
> designed to withstand an EM flux greater than the typical power throughput? On 
> the ground, we use fat braided copper wires and deeply buried rods. That's not 
> an option on a satellite. Thick skin can shield. What else?

The ISS is grounded with a plasma contactor.  It directly connects
system ground to the plasma of the surrounding atmosphere.