[bilsbie]

Hydrogen is diamagnetic (1) so you’d just need the right level of magnetism to repel it (or slightly redirect it)

Or if we shape the field into a buzzard ramjet then you actually take advantage of the interstellar material for fuel.

(1) https://sciencing.com/magnetic-properties-hydrogen-7648446.h...

[foobarbecue]

I imagine you got "autocorrected" but to slow the error propagation I'll point it that it's a "Bussard" ramjet, not "buzzard."

[LorenPechtel]

Well, a Bussard ramjet has been shown to have a maximum possible velocity of .12c. No idea if a buzzard version can do better. :)