Hello,
I've recently started a
blog on the topic of world-building. The blog will follow the my process from defining a solar system to building a life-bearing planet, including geography, ocean currents, alien biomes, & weather. I'll also be linking to my sources, and providing a few tools to make things easier for others.
What may be of the greatest interest is the spreadsheet i've constructed to calculate out a lot of the details based on a few variables.
Once i resolve problems with my FTP, i'll have v 1.1 up which includes the calculations about a moon. Based on Solar mass, distance of planet, mass and radius of the planet and it's moon, and a few other variables, it will describe the orbital periods, goldilocks zone, density, surface area, gravity, roche's limit, and apparent sizes of bodies from the planet, etc.
I'm more of a artist than a mathematician, so i'd also welcome the spotting of any error i may have.
There are two calculations i'd like help with.
TemperatureI have a calculation for temperature that i got off a now defunct website, but it seems rather ad-hoc to me. It produces about the right temperature for earth, but i have little confidence that it works beyond that. BTW this is for terrestrial planets, i'm not expecting a simple formula to cover gas giants too.
T = 374(1-A)I1/4
where:
T = Temp in Kelvins
I = Insolation
A = Albedo
For planets with an earth-like atmosphere, he modifies it like so:
Can anyone confirm that this is on target, or suggest a better formula?
Brightness of a MoonI have the feeling this should be obvious, but can someone provide the formula for how bright a hypothetical moon would be at full? I'm not sure how to work in the moon's diameter. I'm willing to assume that the moon's insolation is the same as the planet's even though it may be a bit further or nearer to the sun as it goes around.