Planet Editor

The Planet Editor is one of Thrive's five editors, and the last to be unlocked. It allows the player to edit a whole planet, including its ecosystem, atmospheric conditions, topography, and the like. The tools needed to unlock this editor are highly advanced, meaning that the player will be well into Space Stage before the possibility of unlocking the Planet Editor is available.

Star Generation

Before the planet can be generated, a star must be generated for the solar system.

For the time being, we will assume all playable solar systems initially form main sequence stars (also called dwarf stars), like our sun. Other types of stars include

• Supergiants
• Bright Giants
• Giants
• Subgiants
• White Dwarfs

Luminosity, Radius, and Temperature

A star's luminosity, radius, and surface temperature are related via the following equation:

L = 4πR²σT⁴

Where:

L = luminosity (in watts)

R = stellar radius (in meters)

T = surface temperature (in degrees Kelvin)

σ = Stefan-Boltzmann constant

The player will be able to set the luminosity and radius of their star. As σ is a constant, this will determine the resulting temperature of the star.

Mass

Using the luminosity, the game can then calculate the star's mass using the following formula:

L_star / L_sun = ( M_star / M_sun )^a

Where:

L_star = Luminosity of the generated star L_sun = Luminosity of the sun M_star = Mass of the generated star M_sun = Mass of the sun a = Is a constant, which is typically set as 3.5 for main-sequence stars.

Lifespan

The luminosity and mass of the star can be used to calculate it's lifespan.

t = 10¹⁰(M_sun / M_star)³

Where:

t = The lifespan of the generated star M_sun = The mass of the sun M_star) = The mass of the generated star

Habitable Zone

The game can then use these values to determine the habitable zone of the star. The inner and outer bounds (in astronomical units) of the zone can be calculated with:

Inner Bound = 0.7R(T/5777)²

Outer Bound = 1.5R(T/5777)²

Where:

R = stellar radius (in solar radii, NOT in meters)

T = surface temperature of the star (in degrees Kelvin)

Additional Notes

Star Generation:

• System Type (Number of Stars: Unary, Binary, Trinary, etc.)
• Luminosity
  • Mass
  • Radius
  • Lifetime
  • Temperature
  • Habitable Zone
    • Choose where the planet exists in this zone.
      • Average Planetary Temperature
      • Year Length

Planet Generation:

• Distance
• Planetary Mass, Radius, Gravity, Density
• Day Length
• Axial Tilt: Determines seasonal variation
• Atmosphere composition (Nitrogen, oxygen, carbon dioxide, argon, hydrogen sulfide, etc.)
• Moons (Affects tidal forces)
  • Number
  • Distance
  • Mass
    • Tides
• Tectonics

Planet Templates:

• Terran Planet
• Sulfur Planet?
• Silica Planet?
• Chlorine Planet?
• Fluorine Planet?

The Solar System

The solar system will start out as a planetary disk. Out of that planets will form, and smash into each other, all of that good Belgium. How it happens. That's basically how you'll have your solar system form. The PE, however will be making planets that are fully fledged.

In The Beginning

You're going to start out with a sizing table, how big you want your planet to be. This will decide size and gravity, however, gravity can be slightly adjusted with a small slider. Gas giants will be made in the same way they were in the old editor, by laying down layers of gases on top of the molten liquid core.

There will be an option to randomize rock layers and landforms on the planet.

Rocky bodies are going to start out as realistic as possible. They're going to be masses of black volcanic rock with cracks corresponding to the gaps between tectonic plates. Tectonics will be a part of your planet, and you'll have continental drift and all sorts of other things that come with the rifts like ocean trenches, volcanoes, earthquakes, etc.

You start to create your planet by building with different layers of rock. You'll have a few panels of rock types- sedimentary, metamorphic, and igneous. You'll have a panel of each type with a few different types of rock on it.

The Rock Cycle will be active as well, so your planet won't stay a granite ball if you make it that way.

Building Controls

Basically, you will have brushes and paint. The brush you select will define how rock is placed, and the "paint" will be a type of rock selected from one of the rock palettes described above. You can also carve into your planet to create canyons, valleys, etc using different brushes. More brushes will populate in small features like hills, small lakes, bluffs, ground covering (except for organisms) etc. You can pour water onto any point on your planet, and also plant springs. You can designate other liquids like liquid methane if temperatures permit*. Different layers of liquid can be poured on, as long as they are of different densities they will not mix.

You can paint biomes on to your planet using brushes. Each brush has a set of rules, and some biomes, including beaches and sea zones will populate automatically.

Static VS Dynamic

Static planets never change from original settings, geologically. In God mode, you should be able to pause organic evolution on a planet as well. Dynamic planets can be affected by geologic activity, disasters, etc, and are constantly in a state of change, like our planet earth. Basically, random things happen to tectonic movement, random asteroids get hurled at your planet, etc.

That's all for now.

*Temperatures are designated by distance from the sun, geologic activity, etc.

Research

https://spec-evo.fandom.com/wiki/Alien_Planets#Geology

Sources

https://cosmicreflections.skythisweek.info/2017/06/08/habitable-zones/