|Antisolar Rays & Rising Moon ~
Taken by Luc Perrot (Photography) close to sunset on 15th January '14 and of course looking eastwards away from the sun. Location: Reunion Island in the Indian Ocean and near the volcano Piton de la Fournaise.
©Luc Perrot, shown with permission
|The rays are bright sky between the long dark shadows cast by clouds in the opposite sky hemisphere.
Unlike most sky optics, antisolar rays (also misleadingly called anticrepuscular rays) are real, they exist in space, they can be flown around or through. They are parallel tubes of dark air crossing the sky that appear to converse towards the antisolar point purely by perspective.
Why is the almost full moon not where the rays converge? The moon's orbit is tilted ~5° to that of the plane of Earth's orbit around the sun. The full moon can therefore be several degrees from the antisolar point. If the full moon occurs at the intersection of the two orbital planes there is a lunar eclipse.