High Sun Antisolar Rays ~ Shetland looking north-east towards Bressay. Chris Brown captured these rays opposite the sun and apparently plunging downwards to a point deep beneath the horizon.  ©Chris Brown, shown with permission.

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The projections of shadow rays onto the celestial sphere follow great circles with the sun and antisolar point at the poles.
Antisolar or 'anti-crepuscular' rays are more familiar near sunset or sunrise. Then, as at left, they are usually formed by clouds near the sun casting long downward shadows right across the sky. The parallel rays and shadows appear, by perspective, to converge towards the antisolar point directly opposite the sun and therefore always below the horizon.

But antisolar rays can also be seen when the sun is high. They might be fainter, shorter and of low contrast but they are there. At sea or on a long beach cloud shadows and rays are often visible all the way around the horizon when the sun is high.