History
The concept of laser propelled vehicles was first formally introduced by Arthur Kantrowitz in 1972. Laser propulsion systems may transfer momentum to a spacecraft in two different ways. The first way uses photon radiation pressure to drive momentum transfer and is the principle behind solar sails and laser sails. The second method uses the laser to help expel mass from the spacecraft as in a conventional rocket. This is the more frequently proposed method, but is fundamentally limited in final spacecraft velocities by the rocket equation.
The forms described below are all of the second type.
Read more about this topic: Laser Propulsion
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