Rapid delivery of small payloads to Mars

To sustain a continued human presence on the surface of Mars or to achieve critical mission objectives the rapid delivery of small payloads may be necessary. Consideration is given to the physics of delivering payloads of about 10 kg over a nominal distance of 1 AU (149.5 x 10 to the 6th km) in 10 days. It is proposed that the most effective method of delivery is the use of a laser lightsail vehicle. The lightsail would be accelerated by a high-power laser from the vicinity of earth to velocities of approximately 174 km/s. Coasting at this velocity for most of the trip the vehicle would be decelerated by a similar laser upon arrival at Mars. The continuous laser power required is calculated to be about 47-billion W and the total duty time of both lasers, determined by optimization of the total energy, is calculated to be 3.9 hours. The laser power scales approximately linearly with payload mass and as the inverse square of the trip time.