Imperial Pulsar Cerulean

From the Latin imperialis, of the empire — applied to color since the medieval period for the hues reserved for sovereigns and empires: imperial purple of Tyrian dye, imperial yellow of Ming-dynasty porcelain. As a modifier, imperial implies saturation combined with the institutional weight of a color owned by a court. Sits in the bold-and-deep corner, alongside royal.

Coined 1968, pulsating-radio-star. As a color modifier, pulsar implies a rotating-neutron-star-and-pulse-beam quality, the visual register of Crab-pulsar-and-Vela-pulsar hand-rotating-neutron-star-and-pulse-beam Crab-pulsar-and-Vela-and-PSR-1919 pulsar-and-rotating-neutron-star-and-pulse-beam surfaces under Crab-pulsar-and-Vela-and-PSR-1919 millisecond-and-radio-and-X-ray neutron-star-light. Sits at the modifier-and-cosmic end of the grid, parallel to nova and mira in usage.

From the Latin caeruleum, originally referring to dark blue paint pigment of the Roman world, then via French céruléen into English. As a modern art-supply name, cerulean blue is the cobalt-tin oxide pigment introduced in 1805. The color refers to a clean, slightly green-shifted blue with the matte finish of mineral pigment in linseed oil: lighter than cobalt, deeper than aqua, with the painter's weight of a word for sky.