There is an interesting article by Andreas Tzoilas about what forms of propulsion would be needed to send a spacecraft on an interstellar mission. And how far we are on in achieving these goals.
Ion propulsion crops up as a candidate for various supporting roles and possibly even as the main propulsion system of the spacecraft.
Having ion propulsion as the primary means of getting around is not a new idea. The development of current ion thrusters are showing that they can be used for interplanetary and near-Earth object missions. Even if the acceleration times are longer.
The VASIMR is a candidate for more powerful thrust. The ideal situation is that it becomes a main propulsion engine.
All this is exciting but it is a far cry from what most people would see a “proper spaceship engine”. TV and films may portray these as fictional superfast thrusters, with glowing lights and sounds but they do have a root in what we would expect a decent engine to be.
For space travel that’s going to be something very powerful that can propel a ship at very high speeds. And putting relativity aside, high speeds may even be faster than light.
This is the type of space propulsion that if ever discovered would make people sit up and think seriously about space travel. In fact the whole Star Trek concept is based on the discovery of Warp Drive and how this leads to man going into space.
So what do we need to do to get to a more powerful propulsion system?
The answer is that we can:
- Develop existing technologies to be more efficient but more power and thrust are needed. That means realistically exploring high energy plasma type devices for one
- Continue to do research into fundamental physics. There is no other choice. Current technologies don’t provide the oomph to realistically travel between stars. We need to understand if it is possible to move matter at great speeds and what energy is needed.
It may sound odd talking about interstellar travel. It may seem hopeful and idealistic in the face of what physics currently says, which is “at the moment we can’t get past the limit of light”.
It’s nice to dream. But then on the flip side it is worth making strides in what we do know, so that we can at least explore the planets in a reasonable time scale. We may not yet be anywhere near the stars but we can try and do so much more within the Solar System.
Even just the Moon!