On Thursday, June 1, 2017 at 2:30:12 PM UTC-4, Robert Clark wrote:
NASA just announced a solar probe to travel quite close to the Sun, about
3.7 million miles from the solar surface:



I was thinking about beamed energy for Earth to-orbit power. The concept is to alter the goals of photon power. Photon inertia is not the only modality. A powerful laser can make an ion trail. And at the same time power a Magneto-hydrodynamic motor. Simple high flux density solar cells would power the magnets for the motor. Of course the flight path has to stay in the ion trail. The most efficient flight path is likely straight up.

Begging the question as to why the laser does not exactly target the center of the MHD motor.. And it does lose ion fuel with altitude, making a nonlinear launch path scenario.

Light source powered MHDs are quite viable. Fuel ions need only be present for free.