Cosmic radiation/Solar flare shielding

How much shielding is necessary to protect electronics etc. from
permanent damage from the particle flux of solar flares? Or, for that
matter, from cosmic radiation?

I'm assuming that most current satellites do not carry the heavy
shielding required to protect them from strong flares (doesn't look
that way from pictures etc.). What happens to them then during heavy
flare activity? Do they just shut down, roll with the punches, and
then get restarted?

What about all these iron particles travelling at almost relativistic
speeds? Surely that can do a lot of damage to electronics?

In article ,
G. Stewart wrote:
How much shielding is necessary to protect electronics etc. from
permanent damage from the particle flux of solar flares? Or, for that
matter, from cosmic radiation?

Depends on what it is you want. The dominant radiation problem for most
space hardware -- which is in low Earth orbit -- is neither flares nor
cosmic rays, but Earth's Van Allen belts. And that problem is minor
enough in LEO that for missions of modest duration, a bit of care in the
circuit design suffices. For long durations, the typical approach is
extra attention to choosing radiation-resistant parts, rather than adding
shielding.

Out in deep space, flares are the major issue. The preference is, again,
to choose radiation-resistant parts rather than attempting shielding,
because shielding is often prohibitively heavy. Occasionally some attempt
will be made to shield highly-susceptible parts, when they must be
included for some reason. It is impractical to shield solar arrays, and
they are simply oversized so that they can tolerate a certain amount of
reduction in their output due to radiation exposure.

Cosmic rays generally are not much of an issue for electronics. They may
cause transient upsets, which require some design attention, but the dose
rate isn't high enough for accumulated permanent damage to be a real
problem.

I'm assuming that most current satellites do not carry the heavy
shielding required to protect them from strong flares (doesn't look
that way from pictures etc.). What happens to them then during heavy
flare activity? Do they just shut down, roll with the punches, and
then get restarted?

Mostly, they notice some small drop in output from their solar arrays, and
their electronics hiccup occasionally. Very sensitive parts like detectors
in some instruments may get powered down at times of high activity, since
damage is less likely with no power applied.

What about all these iron particles travelling at almost relativistic
speeds? Surely that can do a lot of damage to electronics?

There are not enough of them to be a major concern for electronics.
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