The red planet is an iconic feature in our lives today. The beautiful images of its surface sent back by probes and rovers inspire our imagination. It’s such an alien world and presents a striking image. Through research, observation, and rover missions, we’ve worked out what the surface is made from.
1. The red coloration gives it away.
The topmost layer of Mars’s surface, and the material that gives it its tell-tale coloring, is made up of iron dust that has been oxidized. The oxidation essentially rusts it, giving it the reddish color. All of this iron is on the surface of Mars probably because it’s much smaller than the Earth. Our iron sunk down into the core due to gravity, but clearly the same did not happen with Mars. Exactly how Mars had enough oxygen to oxidize the entire surface remains a mystery.
2. Volcanic activity helped shape the surface.
Beneath the iron dust is a mostly volcanic basalt crust. When the rocky interior planets formed, they were hot and molten as they experienced collision after collision. Much of this molten material hardened into basalt. Unlike Earth’s crust, Mars’ is most likely one solid piece since the planet doesn’t experience tectonic activity. This is how those incredible shield volcanoes were able to form into such enormous sizes.
3. Various other materials round it out.
Aside from the iron dusting and volcanic crust, the other abundant materials that make up Mars’ surface are magnesium, aluminum, calcium, and potassium. All fairly commonplace, even on Earth, yet they helped build a world we’re only beginning to scratch the surface of.