it isn’t proven it rains diamonds, just hypothesized! methane and ammonia become very reactive under the immense heat and pressure inside Neptune. the hydrocarbon atoms may separate, which would result in extremely pressurized groups of carbon atoms, which may result in diamonds! https://twitter.com/dreamwastaken2/status/1297509946746122240

diamonds are way denser than any of the material around them, so they would fall down towards the center of the planet, aka diamond rain. there is a chance the “core” of neptune has a ton of diamonds, almost like a diamond surface, but again not proven.

there’s actually a chance the diamonds turn back into liquid carbon, which is super cool. because if there’s liquid, there’s a chance that there’s large diamond blocks floating on the surface, which is super epic.

if they can figure out the carbon properties, we can find out if the gas giants might have solid rocky cores. sadly everything is just a simulation though because only a single mission has flown past neptune (voyager 2) and no more are planned at the moment.

fun fact though! the first atmospheric vortex seen in the 21st century was discovered in 2016 using the HST :D

@dreamwastaken2 you’ll literally never see this thread but the tweet came up on my tl and i wanted to share some facts :))
(and flex my massive brain /j)