Propulsion Technology (3200 AD)

Combustion-based Thrust Drive (CTD)
One of the oldest propulsion systems to be used in outer space, a combustion-based thrust system involves the burning of liquid propellant (fuel, in other words. Older variants of this system use gasoline, newer ones use a combination of gasoline, liquid oxygen and liquid nitrogen). The burning propellant is expelled at extreme speed from engine, producing thrust. The CTD is essentially rocket technology. Top speeds in deep space may reach up to 55,000 kilometers/hour, significantly faster than Ion-based drives. However, the CTD requires a far more demanding source of fuel than Ion Drives do, and as such, is suitable only for use with starfighter-sized craft - anything larger would use far too much fuel to be even remotely cost-efficient. The exhaust from combustion drives has also shown to have a corrosive effect on the ozone layer of planets, meaning that it is best used in outer space only.

Ion Drive
The primary propulsion system aboard any spacecraft larger than 30 meters, the Ion drive functions by expelling a stream of electrically charged molecules from the thruster - resulting in a blue beam of light emitting from the drive of the starcraft. Though they cannot achieve speeds nearly as high as that of combustion-based systems, ion drives are nevertheless the primary form of propulsion for nearly all spacecraft. They are exponentially more economical than CTDs, and they can directly tap into the ship's fusion reactor, meaning that they do not require an external source of renewable fuel like CTDs do.

Hyperdrive
The Hyperdrive is not directly a propulsion system, but is rather an accelerator that propels an already moving starcraft to exponentially faster speeds (several times the speed of light). When thus accelerated, travel between adjacent planets in the same solar system can be reduced to as little as a half hour. Travel between adjacent solar systems requires anywhere between several days and a week, making the creation of small interstellar governments rather easy. While any vessel can include a hyperdrive, the hyperdrive is all but useless without accurate astronomical coordinates. That is where Hyper Lanes come in.

Hyper lanes are mapped-out routes between two systems - travel without following a hyper lane is highly unadvisable, and in all assurance, certainly fatal. Every civilized solar system in the Galaxy is connected to at least one hyper lane, connecting it to an adjacent system. Systems of astrographical value can have as many as four lanes, and serve as hubs, connecting distant trade routes in a grand web of commerce and travel. Such systems often grow wealthy from the taxation, tourism and industry brought in by their advantageous position.

Hyper lanes themselves cannot be attacked, but it is possible to create defensive stations around the lanes point of origin, making it more difficult for an enemy to invade.

Fusion Reactor
In physics and nuclear chemistry, nuclear fusion is the process by which multiple nuclei join together to form a heavier nucleus - it is the same process by which stars release the energy that warms the planets in their orbit. It is accompanied by the release or absorption of energy depending on the masses of the nuclei involved. Fusion power refers to power generated by nuclear fusion reactions. In this kind of reaction, two light atomic nuclei fuse together to form a heavier nucleus and release energy. Until the development fusion power, space travel was simply not feasible - it required far too much energy to be achieved by any other means. Fusion power, a derivative branch of nuclear science, is the sole most abundant source of energy known to mankind. Though they are expensive, all starcraft larger than fighters are equipped with a fusion reactor, of necessity. Fusion reactors are much safer than earlier fission reactors and combustion-based power systems, for damage to a fusion reactor does not cause any sort of violent explosion, but rather simply extinguishes the reaction taking place within. This makes them ideal for use on warships, which are often put into dangerous conditions.