Terraforming

Template:Generic The principle of Terraforming in Aurora is based on changing the atmosphere in order to alter the environment of the planet so it is suitable for your species.

The actual mechanics of using terraforming in the game interface are relatively straightforward. If you have any terraforming installations on a planet or any ships with terraforming modules in orbit, go to the Environment tab, select the gas you want and type the target amount of gas for the terraformers to meet. Make sure to check the Add Gas checkbox if you're adding gas (or uncheck it if you're removing it).

Terraforming Installations are ground-based and require workers. Terraforming Modules are installed on ships in space, and do not require any workers, but do require the overhead of building a ship instead. Spaceborne and ground-based terraforming installations are boosted by the Terraforming skill of the ship captain and governor, respectively.

There are a wide range of gases you can add or remove from an atmosphere, with some being safe (no impact on colony cost) and others being dangerous (colony cost 2-3 minimum if they're in the air at all (VB6) or beyond the safe concentration of that gas (C#)).

Increasing a planet's atmosphere will warm it somewhat, and some gases are greenhouse gases that warm it much more aggressively.

Surface Temperature in Kelvin = Base Temperature in Kelvin x Greenhouse Factor x Albedo
Greenhouse Factor = 1 + (Atmospheric Pressure / 10) + Greenhouse Pressure (Maximum = 3.0)

There is also an anti-greenhouse gas, which can lower a planet's temperature significantly. Mechanics for this differ between versions - see the version pages for details.

The gas your race breathes (oxygen, by default) has some special mechanics. You must have an absolute pressure of that gas within a given range (0.1-0.3 atm, by default), and it must not have a relative pressure above 30%, since atmospheres with too much oxygen can be extreme fire risks. This means that the minimum atmosphere required for safety is 0.334 atm, so you can have 0.1 atm of oxygen, along with 0.234 atm of other gases to keep the relative oxygen pressure down (since 0.1/0.334 = 29.94%, which is below the 30% safety level).

C# additionally contains mechanics related to gases freezing out of the atmosphere, water liquifying into oceans, and terraforming difficulty scaling with body size. See the C-Terraforming article for details.

Gases

This is a table listing all the possible Gases in Aurora 4x (C#) and their attributes. None is the default setting, not adding or removing any gases. This will be automatically selected once a gas has been added/removed to the specified amount. Temperatures are given in Kelvin (0K = -273.15°C). Dangerous Level is the amount at which the gas becomes dangerous in ppm (parts per million). For example, CO2 becomes dangerous at 5000ppm, which is 0.5 parts per hundred, so 0.5% of the atmosphere.

Frigusium and Aestusiumare the main way to decrease/increase the temperature as they are safe (anti) Greenhouse Gases.

Table of Gases

Name	Symbol	Weight	Boiling Point	Greenhouse Gas	Anti Greenhouse Gas	Dangerous	Dangerous Level
None	None	0	0	0	0	0	0
Hydrogen	H2	2	20	0	0	2	500
Helium	He	4	4	0	0	0	0
Methane	CH4	16	109	1	0	2	500
Ammonia	NH3	17	240	0	0	2	50
Water Vapour	H2O	18	245	0	0	0	0
Neon	Ne	20	27	0	0	0	0
Nitrogen	N2	28	77	0	0	0	0
Carbon Monoxide	CO	28	82	0	0	2	50
Nitrogen Oxide	NO	30	121	0	0	2	5
Oxygen	O2	32	90	0	0	2	500
Hydrogen Sulphide	H2S	34	212	0	0	2	20
Argon	Ar	40	87	0	0	0	0
Carbon Dioxide	CO2	44	195	1	0	2	5000
Nitrogen Dioxide	NO2	46	262	1	0	2	5
Sulphur Dioxide	SO2	64	263	1	0	2	5
Chlorine	Cl	35	239	0	0	3	1
Fluorine	F	19	85	0	0	3	1
Bromine	Br	80	332	0	0	3	1
Iodine	I	127	457	0	0	2	1
Aestusium	Ae	40	1	1	0	0	0
Frigusium	Fr	40	1	0	1	0	0