Methods of space travel

Methods of space travel refer to the various ways an empire travels through space.
==Sublight travel==
The below methods are practical mostly for early space faring civilizations.
===Chemical Engines===
Usually liquid oxygen/liquid hydrogen mix which is ignited and shoots out the back of the engine. High thrust but cannot fire for long, running out rapidly. Liquid oxygen and refined kerosene is another mix with even higher thrust, but is even shorter-lasting.
===Ion Engine===
Highly efficient, low-thrust propulsion systems, ion engines create thrust by accelerating ions behind them so they accelerate forwards. Ions are extremely low-mass, so very little thrust is produced. They require large quantities of power to accelerate the ions.
===Electron Engine===
This is a device that uses in electron separation to propel a vessel. Elements with a high number of valence electrons such as many halogens and noble gases are used as fuel. When the engines activate, nuclear fission breaks down the elements causing an explosion that thrusts the electrons outward. Because these electrons travel at almost the speed of light, the vessel accelerates in the other direction, though it never approaches the speed of light directly. Because electrons are so small the momentum of each is tiny, meaning that this system has very low thrust but can continue accelerating for a very long time (ie high specific impulse). This engine is often used to travel between planets within a system.
===Fusion Drive===
This technology uses the energy produced by nuclear fusion to create thrust. This can be direct or through using electricity produced by fusion to power another drive, such as a plasma engine.
Specifics on direct thrust fusion drives are currently murky, but the general idea is to use the energy produced to heat up propellant and expel it from the rear of the craft at high velocity for a high-thrust, high specific impulse system. Fusion confinement can be by a magnetic bottle or inertial where it is hit by powerful pulsed lasers.
===Solar sail===
Relies on solar pressure from other stars to propel the ship to high speeds. A very common form of early interstellar travel. The sail must be very thin and of very great size, making advanced materials science a prerequisite, yet even then produce very little thrust. Naturally, they are incapable of manoeuvre or acceleration in interstellar space without auxiliary thrusters.
A variant uses a powerful laser to exert photon pressure on the sail (beam sail).
===Antimatter engine===
The antimatter engine utilises the energy produced by the annihilation of antimatter. As this produces so much energy for even tiny quantities of reactant, it makes the attainment of very high speeds possible. There are several proposed designs; an antimatter beam core uses the charged pions produced and accelerates them through a magnetic nozzle in a low-thrust but long-lasting drive.
Antimatter solid cores inject antimatter into a tungsten target, which is then heated by annihilation. Hydrogen is pumped past and superheated so that it goes squirting out of the rocket nozzles at very high speeds. Thrust is high, but if you try to sustain the reaction too long the target melts.
===Nuclear explosives force propulstion system (NEFPS)===
The Nuclear Explosives Force Propulsion System (NEFPS) is a method which utilises the force generated by the detonation of a ring of small nuclear explosives released behind the craft. When the bombs explode, the force created pushes on a large pressure plate located at the rear of the craft, propelling it forward. Though at first the spacecraft travels slowly, the vessel, if explosives are detonated at precise intervals, can get to a respectable sub-light speed.
Although never used until the 22nd century, the NEFPS was actually invented by Human scientists in the mid-20th century.
==FTL drives==
FTL drives circumvent the light speed barrier whether it be actually going faster than light itself or by altering the fabric of space.
===Warp drive===
A warp drive works by creating a bubble around the ship, then proceeding to expand space behind it, and contracting it in front. During this process, the ship never even moves. Warp drives are the most common form of interstellar travel.
===Slipspace Utilization Drive===
The slipspace drive is capable of entering interdimensional tunnels created by the gravity wells of stars. While it is faster than a warp drive, intergalactic travel is significantly more challenging due to the general lack of stars in between galaxies.
===Higgsium Drive===
The Higgsium Drive is a faster-than-light drive that works by using the material known as 'Higgsium' (refered to as such because it is composed of the Higgs Particle, capable of changing the mass of surrounding matter) to reduce the weight of a starship to zero, and then uses the ship's fusion core to generate a surge of directional energy backwards, sending the ship forward at FTL speeds varying depending on the drive's intended power. When the ship nears its intended destination, the drive reduces the electrical charge through the Higgsium core, returning the mass of the vehicle to normal, slowing it down to point where it can drift out of FTL into its intended destination, with some margin of error.
Because the Higgsium Drive has a tendency to overheat, ships must regularly discharge into a planet with a strong magnetic field.
===Shift-Drive===
A device that moves the ship partially into one or more of Omni 01's unobservable spatial dimensions. These offer 'shortcuts' in travel by allowing the ship to move through more than the three standard dimensions of space, and so enable travel across interstellar distances in acceptable timeframes. Though the design of the device and the quality of the ship's sublight drives are important in determining the achievable effective speed, generally:
*Moving into one unobservable dimension allows a hundredfold increase in effective speed.
*Moving into two unobservable dimensions allows an effective speed multiplication of one hundred thousand times.
*Moving into three unobservable dimensions offers one hundred billion times the effective speed.
The device is unworkable within solar systems or other gravitational wells.
==Comparison of FTL drives==
Drive name 	Description 	Intergalactic capable? 	Travel time
Higgsium Drive 	Uses Higgs particles to lower the mass of the ship allowing it to go faster than the speed of light. 	The IG-D version can. 	7,000 lightyears per day
Warp drive 	Creates a bubble around a ship. Space in front is contracted while space behind it is expanded. The ship inside doesn't have to move.	If enough power is used, then it's possible. 	5,200 - 8,000 lightyears per day
Slipspace 	Takes advantage of tunnels formed by the gravity wells of stars. 	Possible, if used at the Galactic Core. Currently impractical given the political instability of the region.	10,000 to 15,000 lightyears per day
Shift-Drive (+1D)	Moves the vessel partially into one of Omni 01's unobservable dimensions. 	Insufficient speed. 	Maximum 0.274ly/d (100c)
Shift-Drive (+2D)	Moves the vessel partially into two of Omni 01's unobservable dimensions. 	Insufficient speed. 	Maximum 274ly/d (100,000c)
Shift-Drive (+3D)	Moves the vessel partially into three of Omni 01's unobservable dimensions. 	Yes. 	274,000,000ly/d (100 billion c)
==Other forms of travel==
===Wormholes===
Wormholes are corridors in space-time that allow instantaneous travel between two specified points, circumventing the lightspeed barrier. The larger the wormhole, the more difficult it is to maintain for longer periods of times.
Category:Technology