Called a cyanometer, it is a color wheel featuring 53 different colors for the observer to compare to the sky. A modern version of a cyanometer. (Image credit: Daniel Brown) Ozone blue at twilight ...

Sky blue isn't a new color for Apple. It's the featured shade of the current M4 MacBook Air, a shimmer of cerulean so subtle as to almost be missed. It's silver left too close to an aquarium ...

ST. LOUIS – The sky is always changing colors—from a bright blue on a clear day, to red and orange sunrises or sunsets, or multiple colors of a rainbow—there’s a lot going on that we don ...

The skies of Italy and the Alps, on the other hand, frequently are clear blue. Of all the places which the writer has visited Greece has the purest and deepest blue sky.