At the very top of Venus’s mountains, below a thick layer of clouds, is snow. But not snow as we know it - with some surfaces reaching 480°C, Venus is way too hot for that. So what is this stuff? Researchers have figured out that Venus's heat is vaporising minerals called galena and bismuthinite, causing them to enter the atmosphere as a metallic mist before condensing into a shiny, metallic frost that rains down on the mountaintops.