Full Moon & Shadow Hiding - A full moon imaged over the Sierra Nevadas, California by Andrew Kirk. Images ©Andrew Kirk, shown with permission.

There are no shadows on the landscape close to the full moon. In the lower wide angle panorama there are mountain shadows at left and right. These shadows somewhat paradoxically appear to point inwards towards the moon. Wide angle views taken on the moon itself show similar contradictory shadow directions often upheld as 'evidence' that the shots were staged on Earth.

Shadows are all parallel tubes of darkness but perspective makes them appear to direct towards the antisolar point (ASP) opposite the sun. In this image the full moon is within 3° of the antisolar point. It was not at the ASP at August's "blue moon" because the moon's orbit is tilted ~5° relative to the plane of Earth's orbit around the sun.

When we look in the direction of the ASP shadows disappear behind the objects casting them. The landscape there appears featureless and is brighter than its surroundings due to the absence of visible shadow. The full moon itself is brighter to us for the very same reason - shadow hiding or the opposition effect.

Andrew Kirk has noticed the shadow free zone near sunset creep back and forth along the mountains with the seasons.

The line of sight (red) along the sun's rays, towards the antisolar point, has shadows hidden behind the objects casting them.
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