Solved cryptogram
Mars looks red because its dust is loaded with iron oxide, which is the same stuff as rust.
Astronomy Facts, sourced to NASA.
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What it means
Iron is common in rock everywhere, including on Earth, but on Mars it has oxidized and the resulting fine dust has been spread across the entire planet by wind. The color is a surface coating rather than the color of the bedrock underneath, which is often gray basalt. Rovers grinding into rock have repeatedly found dark, unweathered material a few millimeters down.
The claim comes from NASA.
- SourceNASA
- CollectionAstronomy Facts
- Difficultymedium
- Length72 letters, 19 unique
Nearby in the collection
The facts either side of this one.
About as hard as this one
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