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SESK: Stuff Everyone Should Know · sesk.info/aero-mars-red-rust

Why does Mars look red?

Iron minerals in its dirt rust.

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  1. Red clouds cover its surface
  2. Frozen carbon dioxide coats the ground
  3. Iron minerals in its dirt have rusted ✔

Why: Mars has iron minerals in its soil. They oxidize, which means they rust, and that gives the surface its red color. That is why it is called the Red Planet.

Huh, didn't know that: Ancient Egyptians called Mars Her Desher, which means the red one.

The dad joke
Why is Mars so red? It forgot to wear sunscreen for a few billion years.
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References

Answer: Iron minerals in its dirt have rusted. Mars has iron minerals in its soil. They oxidize, which means they rust, and that gives the surface its red color. That is why it is called the Red Planet.

  1. NASA Science: Mars Facts science.nasa.gov/mars/facts
    iron minerals in the Martian dirt oxidize, or rust, causing the surface to look red.
    Checked 2026-10-10.

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