Page:Project Longshot - Advanced Design Program Project Report.pdf/34



3.2.2 Interstellar Transit
Developing a Propulsion system capable of meeting the 100-year interstellar travel time is the most difficult part of the mission design. 4.3 light years is an easily misinterpreted distance. It is equivalent to 41,000 terra meters (41E15 km) which would take the space shuttle just over 190,000 years (assuming it had escaped the solar system at the speed of Low Earth Orbit). Although 100 years is a long time, this requirement expects a three-order-of-magnitude leap over current propulsion technology.

3.2.2.1 Choosing the System
After the initial inspection of potential Interstellar Drive candidates, it was decided that chemical fuels would not be able to produce a three order of magnitude leap over current systems in the near future. Five alternate technologies were compared for their potential as Interstellar Drive candidates: Pulsed Fusion Microexplosions, Laser-pumped Light Sails, Ion Drive, High Temperature Thermal Expansion of Gas, and Matter Anti-matter Annihilation (see Fig. 3.2a for a summary table). After a thorough inspection of each of the five candidates it was decided that only the Pulsed Fusion Microexplosion was adequately capable of carrying out the mission requirements.