Alit Tart Sky

Old English ā-lihtan, to alight — past-participle of alight. As a color modifier, alit implies a saturated-and-just-illuminated quality, the bright color of evening-streetlamp and Christmas-tree-light freshly-switched-on emission. Sits at the bright-and-warm end of the grid, parallel to aflame and aglow in usage.

Old English teart, sharp-or-acid-tasting. As a color modifier, tart implies a sharp-acid-and-fruit-puckered quality, the visual register of Bramley-apple-and-rhubarb-tart hand-sharp-acid-and-fruit-puckered Bramley-apple-and-rhubarb-tart-and-Yorkshire-orchard tart-and-sharp-acid-and-fruit-puckered surfaces under Bramley-apple-and-rhubarb-tart-and-Yorkshire-orchard Yorkshire-orchard-and-Kentish-Garden-of-England puckered-orchard-light. Sits at the modifier-and-flavor end of the grid, parallel to sour and tang in usage.

The blue of a clear sky at noon — produced by Rayleigh scattering, the preferential dispersion of shorter wavelengths through atmospheric molecules. Air itself is colorless; the color we see is sunlight scattered toward our eyes by every cubic kilometer above. The reference shade is mid-latitude noon under a high pressure system: a clean, slightly green-shifted blue with the luminous depth of light scattered across an entire hemisphere of air.