Solved cryptogram
The atmosphere is a thin skin. Half its mass lies below the height a jet aircraft cruises at.
Earth Science Facts, sourced to NASA.
What it means
Air thins out rapidly with altitude rather than tapering gently, so half of it sits within about five and a half kilometers of the surface. On a globe the size of an apple, the breathable atmosphere would be thinner than the skin. Astronauts consistently describe this as the thing that photographs fail to convey and that seeing it in person changes.
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This is not the kind of claim that goes out of date, which is why it was set as a puzzle rather than a fact with a shelf life.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: 74 letters over 20 different ones, graded medium.
- SourceNASA
- CollectionEarth Science Facts
- Difficultymedium
- Length74 letters, 20 of them different
Nearby in the collection
The facts either side of this one.
- U.S. National Park Servicehard, 72 letters
- NASAmedium, 82 letters
- NASAmedium, 75 letters
- U.S. Geological Surveymedium, 79 letters
About as hard as this one
Scored closest to it by the model behind our guide to solving cryptograms.
- U.S. Geological Surveymedium, 78 letters
- NOAAmedium, 74 letters
- NOAAmedium, 74 letters
- U.S. Geological Surveyhard, 78 letters