User:TheNicestGuy/Science

Stationeers models many of the real universe's physical laws, to simulate the behavior of things like gases, electricity, and stationeers. This is a reference guide to the underlying physical science concepts, and notes on how Stationeers is faithful or unfaithful them.

Measurement

Stationeers measures most properties using units standardized in the International System of Units ("SI"). This applies to the HUD and other visual displays, but it also applies to values used in logic circuitry, which is important to logic-based math.

Mass

Or, Can I Push That?

Mass measures an amount of matter, in terms of its relationship to forces (e.g., gravity), inertia, and acceleration. Stationeers uses the SI unit gram (g) for mass.

The laws of science make two major statements about mass that are relevant to stationeering. First, the amount of force it takes to accelerate an object is directly proportional to its mass. Big things are harder to push, stop, or steer. Second, mass cannot be created nor destroyed, even when it undergoes drastic chemical and physical changes. This second rule is broken in relativistic situations, such as nuclear reactions.

Direct Measurement

Stationeers probably uses mass extensively behind the scenes, within the physics engine to calculate the movement of objects. In the player interface, however, only certain substances are given mass measurements:

• Ingots
• The input contents of crafting machines, and the ingredients of their recipes
• Reagent Mix
• The products of a Reagent Processor (except Soy Oil, which is measured by volume)

Implications

It's hard to say how faithful Stationeers is to the laws of mass, force, and acceleration. For example, it seems unlikely, but not impossible, that the physics engine calculates the total mass of a Stationeer and all of the objects they carry, applying that to the results of player movement.

To be tested: Ships and rovers?

Stationeers is generally very faithful about conservation of mass. The smelting of alloys, for example, always produces the same mass as the ingredients put in. There is an exception due to odd behavior of the Centrifuge; see Metallurgy.

There are currently no nuclear reactions in Stationeers to violate the conservation of mass legitimately. (Despite the name, the Nuclear Cell is really just a super-capacity energy storage device; it does not consume fuel.)

Moles

Or, Will It Blend?

In chemical terms, "amounts" of substance are not measured as mass, but as counts of particles. In Stationeers, the particles in question are always molecules, and the game relates these counts using the SI unit mole. A mole is 6.0 × 10²³ molecules (the Avogadro number). It is abbreviated as mol; Stationeers also uses kmol (one thousand moles) and Mmol (one million moles).

Moles Versus Mass

Although there is a direct relationship between moles and mass, the reason to use moles is because it makes chemistry equations less awkward. Take, for example, the combustion of hydrogen:

2H₂ + O₂ → 2H₂O + a bunch of heat

To apply real amounts of substance to this equation, you can do it very simply as long as everything is expressed in moles.

2mol H₂ + 1mol O₂ → 2mol H₂O

To express the same thing with mass, you would have to account for the very different mass per molecule of hydrogen gas, oxygen gas, and water.

4.032g H₂ + 31.999g O₂ → 36.031g H₂O

The numbers add up (because mass is conserved), but they're odd-looking, and they obscure the fact that the reaction takes more hydrogen than oxygen, molecule for molecule.

Direct Measurement

Stationeers measures all gases and other bulk fluids in moles, so you will see molar readings on, for example, Pipe Analyzers and a Handheld Tablet running the Atmos Analyzer Cartridge. These fluids are found in:

• The atmosphere (if any)
• Enclosed spaces such as rooms
• Pipes
• Pipe-fitted devices such as Furnaces and Tanks
• Portable Tanks
• Gas Canisters

Implications

The game does not include a reference to the molar masses of these fluids, but it should not normally be necessary. Ratios of one substance to another can be crucial (e.g., for Fuel), but these are always calculated by mole (see stoichiometry), not by mass or volume. As such, when you set the mix ratio on a Pipe Gas Mixer, that's a ratio of moles as well.

The game is not faithful to molar chemistry when it comes to the substance called "Volatiles". Volatiles behave in some chemical contexts like pure hydrogen gas (and are sometimes labeled "H2"), but when burned they behave more like a hydrocarbon.

Volume

Or, You Know Where You Can Put That?

Volume is, simply, the amount of space occupied by a three-dimensional shape. If a substance can compress (like a gas), and a container is rigid, then the volume will remain constant even as you pump mass/moles into or out of the container.

Stationeers uses the SI unit liter (L) for volume. Some spaces are more practical to measure in thousands of liters; 1,000 L can be referred to as 1 kL (kiloliter), but it would more commonly be called a cubic meter (m³).

Direct Measurement

Stationeers calculates a volume for everything that can contain gases/fluids.

• Enclosed spaces such as rooms
• Pipes
• Pipe-fitted devices such as Furnaces and Tanks
• Portable Tanks
• Gas Canisters

The exception is the global atmosphere, which is not contained and can be said to have infinite volume^{[verification needed]}.

Implications

The volume of plumbing and other components is not usually made obvious by the player interface, but it is a real and essential factor in calculations of pressure and other properties. Say you produce X mol of gas, and you connect it to a Tank for storage, with no active pumping components between. The more Pipes present between the source and the Tank, the lower the total pressure, because each Pipe adds 100L of volume.

Here are some important reference volumes.

• One large grid cube: 8,000 L (= 8 m³ = 2 meters per side)
• Gas Canister: 64 L
• Portable Tank: 790 L
• Small Tank: 6,000 L
• Large Tank: 50,000 L
• Furnace chamber: 1,000 L
• A Stationeer's lungs: 6 L

Temperature

Or, Will That Cook Me?

Temperature is the measurement of how hot or cold matter is. The precise thermodynamic definition is complex, but it can be roughly summarized as the amount of energy embedded into a substance. Temperature has a very direct effect on pressure, and vice versa.

Thermal energy moves around by three major methods. In conduction, heat transfers directly through matter, tending to bring regions of high and low temperature into equilibrium. (Think "burned by a hot pan".) In thermal radiation, heat generates electromagnetic emissions that can be transmitted even across a vacuum, then absorbed by other matter causing it to heat up in turn. (Think "sunshine is warm".) In convection, conduction heats a portion of a fluid, creating local pressure changes which cause the fluid to move; it carries the heat with it. (Think "hot air rises".)

Direct Measurement

Stationeers measures temperature on two scales. Fluids within plumbing (e.g., pipes, tanks, furnaces) are measured in kelvin (K), where 0K represents the theoretical complete absence of thermal energy ("absolute zero"). Fluids in enclosed spaces or in the atmosphere are measured in degrees Celsius (°C), where 0°C is the freezing point of water at standard atmospheric pressure (101.325 kPa). One kelvin is exactly equal to one degree Celsius, so you can easily convert from K to °C by subtracting 273.15.

Implications

Stationeers clearly models heat conduction in general. For example, a Pipe will gradually conduct heat between its contents and the surrounding matter to reach equilibrium, and this exchange rate is greatly increased by adding a Pipe Radiator. It also models the reality that forcibly "pumping" heat from one volume to another (e.g., with an Air Conditioner or an EVA Suit) requires the use of energy, and also that excess heat is not simply destroyed in this process—it still has to be disposed of somehow.

To be tested: Do different materials have different conductivity?

To be tested: Is thermal radiation modeled? Try in a vacuum.

To be tested: Can fluid flow be induced with heat alone?

Metallurgy

Or, He Who Smelted

Implications

Ores are not measured by mass, but each unit of ore always produces one gram of product (not counting off-gas byproducts) when smelted.

The recipe for an alloy is given as ratios between ingredients, not as exact amounts. These are ratios of mass, not of moles or volume. While this is faithful to real-world metallurgy, the recipes themselves are simplified from their real counterparts.

The total count of the ore units output from a Centrifuge always equals the mass in grams of the mix put in. This is not faithful^{[verification needed]}, because all ores in the game explicitly include impurities. The implication is that the Centrifuge somehow reintroduces the original impurities, and in fact this can be exploited to create those impurities from nothing, if you find them useful.