Solved cryptogram
A single constant predicts every color of light a hydrogen atom is able to emit or absorb.
Physics Facts, sourced to NIST.
What it means
Hydrogen glows in a set of sharp lines rather than a smooth rainbow, and in the nineteenth century the pattern of those lines was fitted to a formula with one constant in it, long before anyone understood why. Quantum mechanics later explained the whole series from first principles. The Rydberg constant is among the most precisely measured quantities in all of physics.
The claim comes from NIST, 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This is not the kind of claim that goes out of date, which is why it was set as a puzzle rather than a fact with a shelf life.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: 73 letters over 19 different ones, graded medium.
- SourceNIST
- CollectionPhysics Facts
- Difficultymedium
- Length73 letters, 19 of them different
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