Mars

Every wonder why Mars appears as a red dot in the night sky? Its hue even gave it its name. Following the Greek tradition, the ancient Romans named it after Mars, their God of War, as it reminded them of the blood spilled on battlefields. Now we know the Martian surface was created mostly by large shield volcanoes. These types of volcano produce large volumes of free flowing lava capable of covering vast areas. The cooled lava became basalt. The minerals in Mars' basalt contain high concentrations of iron. When these minerals combine with oxygen (oxidize), they turn a reddish color similar to rust. Mars has no surface liquid to wash them away. Instead, its atmospheric wind erodes the basalt into very fine dust particles which now cover the Martian landscape. Because this dust contains lots of oxidized minerals, it is mostly rusty in color. Thus when sunlight reflects off its surface, Mars gives off a reddish glow.

Similar soil can be found on Earth too. Hawaii's shield volcano Mauna Kea created similar basalt. Its iron rich minerals have oxidized, eroded and accumulated. Now it so closely resembles the Martian landscape that NASA tests off-world technology on it.