Since I found no topic on this, I took the liberty of creating one.
These Propulsion systems would be created by a type 0 civilization. So it would be in the early game. It would mostly be for Stellar Exploration, and/or Aircrafts.

"We are a Type 0 civilization, which extracts its energy from dead plants (oil and coal). Growing at the average rate of about 3% per year."

- Chemical rockets
- EM propulsion (rail guns)
- Ionic engines
- Fission power


"Type I – this civilization harnesses the energy output of an entire planet.

A Type I civilization would be able to manipulate truly planetary energies. They might, for example, control or modify their weather. They would have the power to manipulate planetary phenomena, such as hurricanes, which can release the energy of hundreds of hydrogen bombs. Perhaps volcanoes or even earthquakes may be altered by such a civilization."

Later more complex and faster propulsion engines would be created and manufactured. These are for a type 1 civilization.
The Theoretical ones are as follows:

- Photonic drive
- Ram-jet fusion engines



"A Type II civilization may resemble the Federation of Planets seen on the TV program Star Trek (which is capable of igniting stars and has colonized a tiny fraction of the near-by stars in the galaxy). A Type II civilization might be able to manipulate the power of solar flares."

Type 2 Civilization would develop these systems. I dont think this game would be able to harbor a type 3 civilization.

- Antimatter drive
- Von Neumann nano probes

"Propulsion systems may be ranked by two quantities: their specific impulse, and final velocity of travel. Specific impulse equals thrust multiplied by the time over which the thrust acts. At present, almost all our rockets are based on chemical reactions. We see that chemical rockets have the smallest specific impulse, since they only operate for a few minutes. Their thrust may be measured in millions of pounds, but they operate for such a small duration that their specific impulse is quite small.

NASA is experimenting today with ion engines, which have a much larger specific impulse, since they can operate for months, but have an extremely low thrust. For example, an ion engine which ejects cesium ions may have the thrust of a few ounces, but in deep space they may reach great velocities over a period of time since they can operate continuously. They make up in time what they lose in thrust. Eventually, long-haul missions between planets may be conducted by ion engines.

For a Type I civilization, one can envision newer types of technologies emerging. Ram-jet fusion engines have an even larger specific impulse, operating for years by consuming the free hydrogen found in deep space. However, it may take decades before fusion power is harnessed commercially on earth, and the proton-proton fusion process of a ram-jet fusion engine may take even more time to develop, perhaps a century or more. Laser or photonic engines, because they might be propelled by laser beams inflating a gigantic sail, may have even larger specific impulses. One can envision huge laser batteries placed on the moon which generate large laser beams which then push a laser sail in outer space. This technology, which depends on operating large bases on the moon, is probably many centuries away.

For a Type II civilization, a new form of propulsion is possible: anti-matter drive. Matter-anti-matter collisions provide a 100% efficient way in which to extract energy from mater. However, anti-matter is an exotic form of matter which is extremely expensive to produce. The atom smasher at CERN, outside Geneva, is barely able to make tiny samples of anti-hydrogen gas (anti-electrons circling around anti-protons). It may take many centuries to millennia to bring down the cost so that it can be used for space flight.

Given the astronomical number of possible planets in the galaxy, a Type II civilization may try a more realistic approach than conventional rockets and use nano technology to build tiny, self-replicating robot probes which can proliferate through the galaxy in much the same way that a microscopic virus can self-replicate and colonize a human body within a week. Such a civilization might send tiny robot von Neumann probes to distant moons, where they will create large factories to reproduce millions of copies of themselves. Such a von Neumann probe need only be the size of bread-box, using sophisticated nano technology to make atomic-sized circuitry and computers. Then these copies take off to land on other distant moons and start the process all over again. Such probes may then wait on distant moons, waiting for a primitive Type 0 civilization to mature into a Type I civilization, which would then be interesting to them. (There is the small but distinct possibility that one such probe landed on our own moon billions of years ago by a passing space-faring civilization. This, in fact, is the basis of the movie 2001, perhaps the most realistic portrayal of contact with extra-terrrestrial intelligence.)

The problem, as one can see, is that none of these engines can exceed the speed of light. Hence, Type 0,I, and II civilizations probably can send probes or colonies only to within a few hundred light years of their home planet. Even with von Neumann probes, the best that a Type II civilization can achieve is to create a large sphere of billions of self-replicating probes expanding just below the speed of light. To break the light barrier, one must utilize General Relativity and the quantum theory. This requires energies which are available for very advanced Type II civilization or, more likely, a Type III civilization.

Special Relativity states that no usable information can travel locally faster than light. One may go faster than light, therefore, if one uses the possibility of globally warping space and time, i.e. General Relativity. In other words, in such a rocket, a passenger who is watching the motion of passing stars would say he is going slower than light. But once the rocket arrives at its destination and clocks are compared, it appears as if the rocket went faster than light because it warped space and time globally, either by taking a shortcut, or by stretching and contracting space."


-J.B.-