Jupiter’s moon Io is one of the weirdest in the Solar System. It’s bright yellow, and this picture is an attempt to show how Io would appear to the average human eye. Io’s colors derive from sulfur and molten silicate rock. The moon’s is constantly being refreshed by a system of active volcanoes. Tides caused by Jupiter’s gravity stretch Io, and the resulting friction greatly heats Io’s interior, causing molten rock to explode through the surface. Io’s volcanoes are so active that they are effectively turning the whole moon inside out. Some of Io’s volcanic lava is so hot it glows in the dark.
Image Credit: NASA