On Earth, snow is frozen water. On Venus, it’s something far stranger. The planet’s surface is scorching—hot enough to melt lead—but its mountain peaks are coated in something bright and reflective. Scientists think it’s a type of metallic frost made of lead sulfide and bismuth sulfide. These metals vaporize at lower altitudes, rise into the atmosphere, then condense and “snow” down onto the peaks. So Venus, the hellish twin of Earth, still has its own kind of winter.