When it became possible to measure the vast distances between Kerbin and its celestial neighbors, the nations of Kerbin came together to create an international system of measurements that would be used for all space related research and activities. The definitions and usage of all measurements are supervised by the International Kerbal Committee of Measurements.

## Length

**Meter (m):**This unit was decided on as the foundation for all length-based measurements. Originally defined by the length of a precisely made platinum-iridium bar, the meter is now more precisely defined as the length of the path traveled by light in vacuum during a time interval of 1/299792458 of a second. This unit of measurement is typically used to measure spacecraft dimensions in the aerospace community.**Kilometer (km):**A kilometer is defined as the length equivalent of 1000 meters. It is typically used to express planetary radii in the astronomical community.**Terameter (tm):**A terameter is defined as the length equivalent of one trillion individual meters. It is used to express distances between stars.**Kerbal****Astronomical Unit (KAU):**A Kerbal Astronomical Unit is defined as the average distance between the center of mass of Kerbin and the center of mass of the sun (Kerbol). This is defined as precisely 13,599,806.454 kilometers. This unit is used to measure distances within a star system, specifically between planets and their stars.**Kerbal Interstellar Unit (KIU):**A Kerbal Interstellar Unit is defined as the distance between the center of the sun (Kerbol) and the center of the Nova Kirbani System (Kirb), the closest star system to the Kerbol System. This distance is defined as the length equivalent of 14.56 Terameters. This unit is used to describe the distance between star systems and other interstellar objects, such as The All.

## Temperature

**Celsius****(C):**The Celsius Temperature Scale, otherwise known as The Centigrade Scale, is a scale of temperature in which 0° is the freezing point of water and 100° is the boiling point of water under standard conditions (101.325 kPa).**Kelvin (K):**The Kelvin Temperature Scale is a scale of temperature at which 0 denotes the lowest temperature theoretically possible in the universe. 0K corresponds to -273.15 degrees centigrade.

## Pressure

**Pascal (Pa):**A pascal is defined as the pressure one newton of force exerts over one square meter.**Atmospheric Pressure (atm):**An atmospheric pressure is equivalent to the pressure exerted by Kerbin's atmosphere on a flat surface at sea level. This is equivalent to 101.325 kilopascals, or 101,325 pascals.