I am working on a 2d game/simulation where planets composed of blocks around a core orbit around a star. They also rotate on their own, and both their rotation around the star and their personal rotation have random velocities.
The program keeps track of when light is hitting which blocks, and their temperature changes over time based on this light. It also colors the blocks differently over time based on their temperature. Hot blocks look redder, cold blocks look bluer.
In the screenshots below, both planets have a counterclockwise orbit around the star and a clockwise personal rotation. The planet to the left/bottom is rotating slowly, while the planet to the top/right is rotating more quickly. I will be referring to them as Planet A (left/bottom in images 1-3) and Planet B (right/top in images 1-3).
This first screenshot was taken as quickly as I could take it after starting the program:
](../../images/3848735923.webp)
Planet A developed very quickly (and retained) a gradient showing warmer blocks on the side that had been in the sun all day, and colder blocks where dawn was just rising. Planet B is moving so quickly, that it seems no real temperature difference can develop.
The second and third screenshots were taken about a minute later, and are only a few seconds apart to better show the strange "banding" on Planet B:
![[Image 2]](../../images/3770158093.webp)
![[Image 3]](../../images/3836742833.webp)
From watching it rotate, Planet B seems to have developed a permanently cold and a permanently hot side, despite its quick (and theoretically even) rotation.
Given enough time, it seems that all planets adopt this strange banding where one side is hot and one side is cold, regardless of the rotation.
(In the screenshot above, taken further along, Planet A is on the right and Planet B is in the middle.)
And the strangest part is that if I let it run for even longer, most planets adopt the sensible pattern that Planet A initially displayed, while some continue the strange banding pattern.
