Maybe it's time to start some research into making Star Trek's deflector shields a reality - not just to avoid being locked into the planet in case of a Kessler Syndrome, but also to make spacecraft of all kind (from satellites over ships to stations) less dependent on (vulnerable and heavy) physical shields.
If only there are deflector shields in reality. Current technologies fail to afford a clear distinction between offensive and defensive potentials, which inevitably leads to controversies and trust issues. Forgive my imaginativeness, if there are effective yet distinctly defensive potentials like deflector shields in reality, I guess most controversies and trust issues will magically resolve by investing most of the resources in this domain to develop such technologies, even though technologies that are not distinctly defensive will still be needed.
Light materials are physically impossible (absorption shield will be heavy anyway), but some energy shield that will deflect radiation could be a solution both for colonies and for spaceships.
Yes, I expect that more advanced active shielding will eventually be developed - particularly since you can detect solar flare events before the radiation arrives.
The challenge with flares is that the radiation can come in from multiple directions, so a cylindrical water container that people can pack into is probably a better defense than just the bulk of the engines.
It starts with something like this https://en.m.wikipedia.org/wiki/Whipple_shield and probably moves on to superconducting magnetic shielding as well. It will have to be defense in depth. There could easily be some kind of liquid layer also so that it's capable of being renewed over time.
It's pretty standard (as in, there are literally standards for it) to have shielding around air-gapped systems and rooms. TEMPEST is a good reference point.
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