The first alternate form of propulsion I will talk about is ion engines. Ion engines work by ionizing gasses and propelling them at a charged grid which slingshots them out, pushing the spacecraft in the opposite direction. Ion engines are not only more efficient than modern engines, they are also faster. However, they may take time to reach such speeds, and can only be used in the absence of ions making them impractical for use anywhere but space. This means that they would need a conventional engine to put them in orbit, unless they start there.
One problem with ion engines is that we would need to provide plasma, and electricity for the drive to work. There is also the problem that I mentioned earlier about the fact that they can only be used in space. Of course this problem could be avoided by building “docks” in space capable of building and harboring spacecraft that use ion engines, and then just shuttling passengers down to the planet, and back up again, along with supplies to build the ships. Ion drives have been used for satellites but not much else.
- My first question is: how much does an ion engine costs to build, repair, and operate compared to modern forms of propulsion?
- My second question is: how long do you think it will be before most spaceflights are made with ion engines?