6 Responses

1. Warp drives are purely science fiction at the moment, but may be possible with future technology.

   Ion propulsion is possible, and they are called Ion Thrusters. They use an electric field to accelerate charged particles (ions) out the back of the engine, which provides the thrust. They were said to be the engines of the Tie Fighters in Star Wars, but the maneuvers they perform in the movie are unlike anything they are capable of in real life. In reality, they are vastly more fuel efficient than traditional liquid fuel rocket engines, but suffer from horrible acceleration.

   I can’t think of any other types that would be considered “exotic.” Rocket engines are by far the most common at the moment.

2. SVAL is right that ion propulsion is already in use. It has extremely low thrust but is extremely efficient. And the low thrust is no problem in space where there in no friction and you can thrust for weeks or months at a time to build up speed slowly.

3. Nuclear populsion is used with long range probes, and can reach sustantial speeds over time.

   So far, that is our best technology, and still far too slow for interstellar space travel.

4. There are ion engines that prdouce a low thrust, but in space there is no resistance, therefore nothing to hold back the space craft. This form of propulsion is also very efficient, fuel wise. Next there is nuclear propulsion known as NERVA, NUCLEAR ROCKET ENGINE FOR VEHICLE APPLICATION) was originally developed in the 50’s and 60’s. The weight of the reactor and the political envirnment of the time guarenteed that nuclear would not be an option in the present or near future.

5. Although only theoretical at the moment one exotic drive I like is The Bussard ram drive:

   Starting an engine like this anywhere near an inhabited planet would be problematic.

   Initially using a conventional propulsion system to get started, once up to speed our spaceship would deploy a magnetic scoop for miles ahead of it.
   This scoop would collect free hydrogen molecules plentiful in space.
   Compressing the hydrogen as it is funneled around our ship the hydrogen would ionize providing us with a shield against damage from encounters with particles. A real problem when traveling at relativistic speeds.
   The magnetic field compresses the gas untill a few miles behind the ship the hydrogen fuses creating a mini-sun.
   The energy released by the mini-sun contained in our magnetic bottle is released to the rear to provide thrust.

   This should get you up to interstellar speeds pretty fast.

   Halfway thrugh our journey we shut down the sun to the rear and ignite one off our bow to slow down. It takes as much time to slow down as it does to speed up.

6. warp drive