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.
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, and the page it comes from was read on 2026-08-27 to confirm it still says this.
This is not the kind of claim that goes out of date, which is why it was set as a puzzle rather than a fact with a shelf life.
Solve it yourself
This fact is a cryptogram here: 72 letters over 19 different ones, graded medium.
- SourceNASA
- CollectionAstronomy Facts
- Difficultymedium
- Length72 letters, 19 of them different
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