Calculate Planet Density

Input the amount of water, iron and silicates the planet has in terms of Earth.

How the program works

Here's all the steps the program takes to output the various data you will see below:

1. You input the number of Earth's worth of water, iron and silicates the planet has.
   • In each input field, enter the number of Earth's worth of each material you want on your planet. Entering "1" in the input field for water represents 1 Earth's worth of water, which is about 1.4 x 10¹⁸ tonnes (1 tonne = 1000 kg), or 0.023% of the Earth's mass.
   • If you wish for the planet to not have that specific material, leave the input field empty, or enter 0. Otherwise, enter a positive number into the field to represent how many Earth's worth of that material you want for your planet.
   • If you wish for your planet to have the same composition as Earth, make sure the input fields have the same number.
   • For the program to work, the planet's mass must be above zero. Make sure at least one of the input fields is filled with a positive number.
2. Those three material values are all multiplied by the percentage composition of each respective material on Earth. They are then added together to get the planet's total mass in Earth masses.
   • Water = 0.023% of Earth's mass
   • Iron = 35% of Earth's mass
   • Silicates = 64.997% of Earth's mass
3. The three material values and the planet's mass are multiplied by the Earth's mass in kilograms to get the mass of water, iron and silicates and the mass of the whole planet in kilograms.
4. The three material values are divided by the mass of the planet in kilograms to get the percentage composition of the planet.
5. Those percentage values are multiplied by the densities of their respective materials (in g/cm³) to get the average uncompressed density of your planet.
   • Water = 1 g/cm³
   • Iron = 7.87 g/cm³
   • Silicates = 3.23 g/cm³
6. The uncompressed denity of your planet is multiplied by the uncompressed density of Earth as calculated in this program to get the density of your planet in Earths.
   • This is a better baseline for the density of your planet, as it approximates the compressed density of the planet, as it puts it in terms of Earth's density as calculated in this program.
   • This enables a better approximation of the planet's radius from its mass and density.

The densities of the materials and the mathematical methods of calculating the planet's density are inspired by Artifexian's Video "Terrestrial Moons", which discusses the various components of a moon, including the compositions and densities of said moons for the purpose of worldbuilding.

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