Propulsion Scales (Earthfleet)

In the Earthfleet Universe, there are a number of different ways in which the various races determine the current and maximum flight speed of a vessel at both sublight and FTL. Some of this depends on the actual propulsion system being used, and some on the race that is using it. Listed below is the most common systems of speed measurement used within the galaxy, both standard and unique.

Earthfleet - AUT

In the Sol Sector, where Earthfleet operates, the primary measure of speed is the AUT or "Astronomical Units over Time". This uses the globally accepted "Astronomical Unit" as its chief form of measurement for both distance, and speed measurement when traveling at either FTL or sublight. An Astronomical Unit is the average distance between the surface of the sun (the Earth's distance to the sun varies depending on the time of year) and Earth. An AU is measured in several ways. It's roughly calculated as being 149,597,900 Kilometers or 92,955,810 miles, depending on your preferred method of measurement. At light speed (about 186k miles per second) it takes roughly 8 minutes and 20 seconds to cross this distance. This measurement of speed is then broken down by increments of hours, minutes and seconds. So 100AUH is 100AU per hour, which is roughly 92,955,810 miles X 100 / 186000 = 49,976.24 light seconds, 832.94 light minutes, or 13.88 light hours.

In short, a ship traveling at 100AUH would travel the same distance in an hour that it would take light 13.88 hours to cross. At this speed a ship would be traveling at 13.88 light seconds per second. As another example, a ship moving at 5AUM (5AU per minute), which would be the equivalent of 300AUH, would be traveling at 2498.81 light seconds per minute, or 41.33 light seconds per second. It would take light about 41.64 minutes to cross that same distance. And, as a final example, a ship traveling at 10AUS would travel 4997.62 light seconds per second. That's 83.29 light minutes per second or 1.388 light hours per second. At that speed, a ship could travel 119,923.2 light hours per day. That's 13.6 light years per day. At that speed it would take a ship 7352.94 days to cross the entire width of our galaxy.

Warp Speed - Galactic Standard Scale

Unlike with Coaxial and Hyper Drive, Warp Speeds are determined by power scales, with each step being exponentially higher than the previous one. Each step on the warp scale also corresponds to a multiplier of light speed. For example, warp 1, being the baseline metric, is equal to the speed of light. All other metrics above this are exponential in nature with Warp 15 coming in at a staggering 473,364 times the speed of light. This is roughly 0.9 light years per minute. Not every warp powered ship can reach this speed, but a fair number of elite military vessels within the galaxy have the capability to reach this speed. In Warp speed terms, this roughly equates to having the peddle jammed into the firewall with the engine operating at maximum possible output. Anything faster and the ship risks catastrophic rupture of the warp nacelles due to plasma over-pressure.

Grand Scale

The Grand Scale, while older, is still commonly used within the galaxy by numerous races who operate FTL drive systems that are not scale denominated like Warp Drive, or denominated in Astronomical Units, such as in Sol Space. Typically, Hyperdrive and similar FTL systems use this method to express their observed velocity at FTL. Speeds on the Grand Scale are denominated according to the standard galactic calendar, which is 360 days long with speeds being denoted in "Light Years Per Standard Day", with a standard day being 26.5 Sol hours. So, for example, if you were traveling at a speed of 15 light years per day, your speed would be considered to be 15GS. In Sol time, that would be an equivalent speed of 13.59 light years per one Earth day.

Other Scales

There are a variety of other, lesser used scales that can be found all across the galaxy. For example, with the Razkor, as their primary FTL drive system is the Jump Drive, their "speed" is denoted in distance traveled per jump. For a handful of the races who prefer to use Slipstream or Hyperluminal FTL drive systems, they measure speed by distance traveled, but denominate their distances in sectors and parsecs, rather than Light Years, per standard galactic day. So if you were going 9Sec, your would cross 9 complete sectors of space in one day. To go 3.4PS means you've crossed 3.4 parsecs. If you go 3.4Sec, then you've crossed 3 sectors and 4 parsecs, with a galactic standard sector being 15 parsecs wide, and a parsec being 3.97 light years. There are also a number of other, less commonly used scales, most of which are derived from local or regional scales of distance and time that do not directly correspond to galacticly accepted standards of measurement.