No need for a Dyson sphere. Theoretically, you could place a relatively small, dense object fairly close to Betelgeuse and protect your entire stellar neighbor

No need for a Dyson sphere. Theoretically, you could place a relatively small, dense object fairly close to Betelgeuse and protect your entire stellar neighborhood. I haven't done the math, but I suspect it would have to be so small and dense that it would be a black hole. You'd probably be better off just trying to shield your planet from whatever lesser energies eventually arrive.