Feasibility study of a laser launch system for picosatellites and nanosatellites in low-earth orbits

摘要

Laser propulsion is a space transportation system that obtains thrust from a laser beam that is transmitted from the ground as an energy source. In this study, we evaluated the launch performances of two types of laser propulsion systems in a circular orbit at an altitude of 500 km. One propulsion used the heating system of the laser-sustained plasma (LSP) type, and the other propulsion had the heating system of the porous-carbon heat exchange (hereinafter PHX) type. Assuming a laser power of 500 kW, which is the maximum laser power that is commercially available, the payload masses were estimated to be 0.679 and 0.640 kg for the LSP and PHX systems, respectively. This result shows that the laser power level that is currently available enables the launch of a picosatellite. The laser power values required to launch a nanosatellite less than 10 kg were estimated to be 6.8 and 6.4 MW for the LSP and PHX systems, respectively. Finally, the launch cost was estimated as a function of the number of launches. Our results show that, when the picosatellite was launched 1000 times, the launch cost became comparable with that of a conventional nanosatellite launch. Subsequently, the launch cost decreased to one-twentieth the cost of a conventional chemical rocket.