http://apcnasa3ozl2j74htizuzba5b6nhugbg2qze2nrz43siunkct555fpid.onion
As long as "hole" in sail is < 1/2 the light wavelength, the sail appears solid to incoming photon) "Perforated" Solar Sail - Similar to microwave "hole" concept, but for Solar / Laser Sail (Holes ~0.2 µm) Magnetic Sail (MagSail) (Momentum from solar wind "pushes" against magnetic field produced by MagSail, which is actually a ring of superconducting cable) Particle Beam (Macroscopic pellets or microscopic particles "push" vehicle) Various analogs to MagSail (charged particles) or Solar / Laser / Microwave...