[Spaceships] Magsail acceleration question

[malloyd]

The "sail" isn't physical, not even in the classic design. It's a volume around the current carrier limited by how far the magnetic field can reach. As the density of the particle wind goes down, the field can reach further away from the physical loop. It is after all the point to induce motion in those charged particles, and moving them sets up counterfields. The denser they are, the closer to your spaceship those induced fields will screen the rest of the universe from the field of your magsail.