Real Atmospheres

Atmospheres, hazes and clouds for Kitten Space Agency's Solar System, derived from each body's composition and particle optics, with flight atmospheres from measured profiles. A StarMap mod.

No game files are modified: the mod loads patched copies of the game's shaders and system data at launch. Use the release built for your KSA version.

Download

Borea

GitHub

Features

Clouds

• Volumetric clouds stay in view from much higher up before the 2D layer takes over
• Extended cloud self-shadowing

Flight atmospheres

• Drag and engine back-pressure follow measured density and pressure profiles on Earth, Venus, Mars, Titan, Jupiter, Saturn, Uranus, Neptune, Triton and Pluto
• Each atmosphere ends at its real height

Earth

• Gas density from the US Standard Atmosphere 1976
• Ozone layer shaped after the same standard

Mars

• CO₂ Rayleigh scattering, with density from Pathfinder and Phoenix
• Dust scattering from Mie theory, giving the blue sun halo and blue sunsets
• Dust that thickens into the basins
• Water-ice cirrus at 22–29 km

Venus

• Dense CO₂ atmosphere, with density from the Venus International Reference Atmosphere
• A single solid cloud deck at 48–72 km, in Venus's measured pale cream
• Opaque clouds from orbit, with subtle darker markings
• Clouds that circle the planet in about four days
• Blue-absorbing haze that thickens toward the cloud base

The giants

• H₂/He Rayleigh scattering at its real strength, from each planet's composition and measured gas density
• Volumetric cloud decks that keep their brightness from close up to orbit
• Cloud maps that flow with each planet's winds

Jupiter

• Bright zones high and dark belts low in the volumetric clouds, with deep vortices
• A thin stratospheric haze

Saturn

• Volumetric clouds, with cloud height following the planet's map
• A thin stratospheric haze
• Methane colouring
• 2048 px colour map

Uranus and Neptune

• Volumetric clouds, with cloud height following each planet's map
• Methane absorption and a thin haze
• 2048 px colour maps

Titan

• Golden haze from Huygens and Cassini measurements
• Haze-to-gas transition from Titan's measured density curve
• Disc colour matched to Titan's measured spectrum
• Stratified upper haze with detached layers, animated with simulation time
• White methane clouds in two polar caps

Pluto and Triton

• N₂ atmospheres and hazes from New Horizons and Voyager measurements
• Hazes that show as a bright ring when lit from behind
• Stratified haze bands, animated with simulation time
• Nitrogen-ice clouds on Triton

Terrain and moons

• A softer terminator on rugged ground with little or no air
• A planet keeps its full detail while a small moon passes the camera

Settings

With ModMenu installed, the game's Mods menu has a Real Atmospheres page:

• Procedural haze bands: the animated bands in the haze of Pluto, Triton and Titan. Unticked, their haze is smooth.

Settings are saved in RealAtmospheres\settings.toml in the game's documents folder.

Installation

Requires StarMap. Each release is named with the KSA build it was tested on.

With Borea: install Real Atmospheres from the mod list.

Manually:

1. Install StarMap and run the game once through StarMap.Loader.exe.
2. Extract the release into Documents\My Games\Kitten Space Agency\mods\, giving mods\RealAtmospheres\RealAtmospheres.dll.
3. Launch the game once and close it. KSA adds new mods to manifest.toml disabled: set this mod's entry to enabled = true.
4. Launch through StarMap.

To uninstall, delete mods\RealAtmospheres and mods\_RealSharedShadow.

Building

deploy.ps1 builds the mod and installs it into your mods folder. package.ps1 -Version x.y.z -GameBuild vYYYY.M.D.NNNN builds a release archive in dist\. Set StarMapDir to your StarMap folder.

Credits

• Saturn map mixed by JCP-JohnCarlo, from work by HellcatF6F, MrSpace43-Celestia, FarGetaNik and Snowfall-The-Cat.
• Uranus map by Askaniy, CC BY-NC-SA 3.0. Our modified Uranus map, cloud mask and flowmap are released under the same licence.
• Neptune map by Askaniy, CC BY 3.0, modified.
• Mars cirrus, Titan haze and cloud, and Triton cloud masks: Produced in part with SpaceEngine PRO © Cosmographic Software LLC.
• Mars dust scattering after S. Schneegans, T. Meyran, I. Ginkel, G. Zachmann and A. Gerndt, "Physically Based Real-Time Rendering of Atmospheres using Mie Theory", Computer Graphics Forum 43(2), 2024.

The code is MIT. Because of the Uranus map, the release as a whole is for non-commercial use. CREDITS.md gives the source and terms of every shipped file.