Moon

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Revision as of 11:07, 19 March 2016 by Sapphire (talk | contribs) (added atmosphere, gravity field, etc. Corrected some wording associated with planets to "moons". Some information may need to be double checked for accuracy!)
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Moon Moon01.jpg




Overview

Moons are destructible voxel objects with their own Gravity field, atmosphere, possible vegetation, and hostile life. They are similar to Asteroids in that they're fully destructible voxels, and have randomly generated Ores but that's where their similarities end. Moons range in size from 19km to 38km, however they can be Planet sized 120km in diameter (only if spawned in manually). By default, each moon is accompanied by a Planet, unless manually spawned in by a player. Moons and planets are exactly the same objects technically and are very similar in practice, with a few key differences being: Moons are much smaller often only 38 km in diameter and possess much weaker gravitational fields - down to 0.25 G.

Much like Asteroids they are completely immobile and never will move no matter how much force is applied, and are themselves not in anyway affected by gravity. If two planets were spawned very close to each other inside both of their gravitational fields, neither of them would ever fall into each other and meet. Although objects would experience some very strange gravitational effects from both of them.

Surface Generation

While their surface appears randomly generated, they're in fact pre-loaded voxel models. There is no procedural generation with Moons or planets. When the size of the Moon is increased, it actually stretches the models to accommodate for the new size. The textures and vegetation aren't stretched, only the surface model is. Each Moon type Earth-Like Moon, Europa, and Titan will spawn the appropriate models and surface textures associated with them. The same properties are applied even when it is spawned in manually by the player via (default) - SHIFT+F10 in Creative Mode.

Ore Generation

Cobalt Ore Icon.png Gold Ore Icon.png Ice Icon.png Iron Ore Icon.png Magnesium Ore Icon.png Nickel Ore Icon.png Platinum Ore Icon.png Silicon Ore Icon.png Silver Ore Icon.png Stone Icon.png Uranium Ore Icon.png
Cobalt Ore Gold Ore Ice Iron Ore Magnesium Ore Nickel Ore Platinum Ore Silicon Ore Silver Ore Stone Uranium Ore
Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes

Surface

(~15 to ~50 Meters): Large horizontal veins of Ores with a thickness of a few meters. Each ore patch usually contains 1-4 ores. Different ores of the same patch can be found in different height levels. The surface above the ore patches is slightly darker and in a brown-ish color, so they can be easily spotted from a higher position. All ice lakes on the surface of a Moon contain Ice ores.

Boulders

The Ore is hidden inside stone rocks that are spread randomly over the surface. Boulders are all about the same size, they contain about ~20,000 of rare ores up to ~100,000 of iron ore. Under certain conditions, the positions of non-drilled boulders are reset completely, so GPS-Markers on these rocks become void. The rocks are also voxel entities that are separate from the Moons voxels. They do overlap the moon in the way that station blocks do.

Atmosphere


Different Moon have different atmosphere densities, some with none at all. All thrusters behave differently in a moons atmosphere[1]. Moons with less dense atmospheres the less effective Ion Thrusters for example are and they operate with higher output. Atmopsheric Thrusters on the other hand increase in effectiveness the more dense the atmosphere is. <A general explanation of how a moons atmospheres and its effects work.>

Ion Thrusters

Ion Thrusters (Large Thruster), vary linearly in effectiveness from a minimum of 30% near the surface of a moon with a thick atmosphere to full 100% effectiveness out of it. Planets or Moons entirely without atmospheres will have Ion Thrusters operate at full effectiveness.

e = effectiveness of Ion Thruster as a percentage
r = current altitude/distance from the core of the planet in meters
R = radius of the moon in meters
A = 'LimitAltitude' effectively defining the height of the atmosphere.
H = The 'Hills' Parameter - it's found in the planet's sbc file, 
    it loosely correlates to the maximum height of any mountain/hill as a ratio.
    Typically this is exactly '0.12'.

           (r - R) 
e =   ( ------------ ) x 0.7 + 0.3
         (R x H x A) 

Atmospheric Thrusters

Atmospheric Thrusters act almost inversely with Ion Thrusters, while thick atmospheres are disadvantageous to Ion Thrusters - they are advantageous to Atmospheric Thrusters. They operate anywhere 100% at the moon's radius or 'the surface' to 0% effectiveness (providing no lift or propulsion) when they leave the atmosphere of the moon. They require an atmosphere to operate, whether breathable or not.

e = effectiveness of Atmospheric Thruster as a percentage
r = current altitude/distance from the core of the moon in meters
R = radius of the moon in meters
A = 'LimitAltitude' effectively defining the height of the atmosphere, typically 2.0
H = The 'Hills' Parameter - it's found in the moon's sbc file, 
    it loosely correlates to the maximum height of any mountain/hill as a ratio.
    Typically this is exactly '0.12'.

               (r - R) 
e = 1 - ( ----------------- ) 
           R x 0.7 x H x A 

Gravitational Field


g = the current acceleration due to gravity felt at r (the current altitude away from the core) in m/s^2 (on the surface it should be 9.81 m/s^2 or 1 G)
r = current altitude/distance from moon 'center' or core in meters.
R = the predefined Radius of the moon [Typically 60 km] in meters.
H = The 'Hills' Parameter - it's found in the moon's sbc file, 
    it loosely correlates to the maximum height of any mountain/hill as a ratio.
    Typically this is exactly '0.12'.

if r > R x (1+H)       g = 9.81 x(R x (1+H)/r )^7   [Gravity after the "hills" parameter attitude decreases exponentially]
if R <= r <= R x (1+H) g = 9.81                     [Gravity remains 1 G until, your attitude is greater than the Hills Parameter attitude]
if r < R               g = 9.81 x ( 1 - r/R )       [Under the 'surface'/radius of the moon]

Once the gravity of the planet or moon (in units of G), reaches 0.05 G or gravitational acceleration is less than 0.5 m/s^2 anything beyond this range is no longer affected by the moon's gravity and has completely escaped it's gravitational influence. This distance is much shorter than in reality for actual planets & moons, making actual high altitude low-speed orbits impossible - although it is possible to park a station in place at this point to act as if it were in Geosynchronous orbit.

Gravity Generators (Gravity Generator, Spherical Gravity Generator) and Jump drives are negatively affected by the presence of natural gravity from planets and moons, which for Jump Drives renders them completely inoperable - the presence of any Natural Gravity that is sufficiently detectable (greater than 0.05 G) cannot be 'jumped' into or out of. Gravity Generators will still operate in natural gravity but at increasingly reduced effectiveness the stronger the natural gravity becomes.

<A general explanation of how planet/moon gravity and its effects work. Heavily detailed information about natural gravity should go into the link below> [2]

Moon Variants

<Explanation of moons having different types>

Earth-Like Moon

<Summary here>

Europa

<Summary here>

Titan

<Summary here>

Natural Gravity

<A general explanation of how moon gravity and its effects work. Heavily detailed information about natural gravity should go into the link below>

Thruster Behavior

<Explanation on how natural gravity changes the behavior of Ion thrusters and how they differ from Atmosphere ones>

See Also

Known Issues

Update History

References

  1. http://forum.keenswh.com/threads/atmosphere-falloff-and-thruster-types.7373331/
  2. JoeTheDestroyer - http://forum.keenswh.com/threads/does-the-source-on-github-actually-contain-the-planets-release.7373953/