Low energy trajectories
Cargo could be inserted into low-energy trajectories. These trajectories will take longer then current Hohmann transfer orbits, but will save propellant and thus allow more payload. Low cost of transport will be vital in setting up a colony and in resupplying a semi-autonomous colony.
- Bi-elliptic transfers
- The Interplanetary Transport Network
- Using ion thrusters/solar sails/plasma sails
- Such trajectories will take much longer then Hohmann transfers
- This means cargo will be exposed to the harsh conditions of space for a longer period of time. New and ingenious methods will be needed to solve this.