Been thinking about writing a solarpunk story about a far future where humans live on this habitable Earth-like moon, but I’m wondering how the weather would work if the Earth-like moon is tidally locked to a gas giant and thus one day on the moon corresponds to a full orbit which would be like longer than an Earth week. So parts of the moon would be in night for several Earth days long, and other parts would be regularly eclipsed by the massive gas giant as well, making a sort of night.
How would the weather work in such a case? Would it freeze every night on this world? Or would winds and atmosphere still regulate temperatures?
I think as an example you should start looking at polar latitudes on our planet. They experience long periods of sunlight and night over the course of a year week-long solar days are comparatively short. Temperature is largely moderated by the atmosphere. The reason the moon has it’s massive swings is because it lacks an atmosphere to even things out.
Another thing to remember is that the planet-side is going to be much brighter almost constantly. Gas giants tend to have high albedos, meaning they reflect a lot of sunlight. They will also look large in the sky (Jupiter from Io would be about 15⁰ I think). I think it would be a radiant heat source in its own right, depending on it’s temperature.
Well, it’d reflect light on the sun side.
Well sometimes the whole moon would have light, half from the sun, half from the planet. What would the line between the two be like? You think the reflected light from the planet would be brighter than the direct sunlight?
Often the whole planet would be dark, hidden from the sun behind the planet. The shadow as it transitions is interesting, as well as when parts get both sunlight and planet light.
Is there a way to make the atmosphere thicker to make temperatures more consistent? I assume you don’t want all the characters to be aquatic.
Thanks for the tips!
It sounds like a really interesting place to live. Long days and nights on the outside side while the planet-facing side would only get a varying glow from the planet and sort of an incomplete sunrise and sunset. Depending on how warm and reflective the planet is, it might be dusk during the day, then a sort of sunrise, then a total eclipse, then another sunrise and back to dusk. Rad.
From a weather standpoint it sounds kinda turbulent. The smaller size/thermal momentum of the moon’s atmosphere, and the inconsistent heating could give you some stronger temperature swings week to week (plus one side of the planet would be more effected than the other). The temp changes could effect all kinds of stuff depending on stuff like mountains and bodies of water. Maybe hurricanes and tornadoes, or heavy rainstorms? I wish I knew enough to be more specific.
I will check: do they have a molten core protecting their atmosphere with a magnetic field, or is it something the terraformers built? If so you could justify Aurora borealis (or alternatively sweet volcanos and geothermal). If it’s tech protecting them, that could back up some of the themes of solarpunk respecting nature but still using technology, which I suppose is somewhat there already if they used space trave to get to this moon (though that might have been a different, more exploitative society that they’ve reformed since).
I’m looking forward to seeing what you come up with, sorry I’m not better at weather stuff but if you want help with other world building or want a test reader let me know.
Actually I developed the time system before I developed anything else. 😅 As the gas giant is quite large, eclipses are common.
I’d like a small magnetosphere like one of the Jovian moons. There’s a proplanetary hemisphere (tidally locked to the planet) and an antiplanetary hemisphere (facing away from the planet). Then there’s a leading hemisphere that faces toward the direction of the orbit and a trailing hemisphere opposite. So turns out a moon has a lot more hemisphere divisions than a planet.
I’m interested to see the experience of living there!
Maybe this isn’t useful but I’ve generally had pretty good luck asking worldbuilding questions in specialized communities here and on reddit. Sometimes people are really excited to jump into hypotheticals and sometimes I find myself trying to explain the concept of fiction, it’s always interesting seeing which communities go which way.
There’s a weather community on Lemmy and a meteorology subreddit (if you have an account over there) maybe they’d be able to make some more suggestions?
Best of luck!
Thanks!
Yup already did, but their work on habitable moons are a bit lacking.
