Astronomy Facts

The solar system and what lies past it, cited to the missions that went out and looked.

30 cryptograms, each one a fact written for this site rather than a sentence taken from a book. Cited to NASA and Royal Society of Chemistry.

How they are kept honest

Every claim names where it came from, and every source was read on the day it was cited, between 2026-08-27 and 2026-08-27. 3 of them can change over time and carry a date by which somebody should check them again; the rest cannot.

How hard they are

5 easy, 18 medium and 7 hard, graded by the model described in our guide to solving cryptograms.

They average 73.9 letters over 19.1 distinct ones, with 3.8 letters appearing exactly once.

Every one of them

Each has a page of its own naming its source, and its answer on a separate page so you will not run into it by accident.

Other fact collections

Play a cryptogram

All fact collections · Collections from books