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Type I Kardashev civilizations, like ours, might build megastructures large enough to cover a planet with writing for orbital readers, as suggested in 1826 by Carl Gauss (who proposes to plant wheatfields on tundras so as to convey axioms of geometry to lunar aliens).⁴² Just as Percival Lowell might have misperceived canali criss-crossing the plains of Mars, mistaking illusory channels for evidence of artificial irrigation during his telescopic monitoring of the planet,⁴³ so also has Richard C. Hoagland argued that (despite evidence to the contrary from NASA), the Cydonia Planitia on Mars displays evidence of intelligent inscription, including monuments and pyramoids, all arranged in significant geometrical patterns.⁴⁴ When zooming into these features with orbital cameras, however, the pareidolia of their artificiality disappears into natural geology.