3 in 1 - "Taken Memorial Day, May 31, 2010, at Bishop, California. The last rays of the sun shine on an alfalfa field, with anticrepuscular rays/shadows and foreground shadows all apparently pointing to the anti-solar point marked by a heiligenschein. Hugely exciting to witness."  ©Andrew Kirk, shown with permission.
Atmospheric
Optics

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The antisolar point directly opposite the sun, also named the subanthelic point, is a favoured direction for atmospheric optics.

Sun rays and shadows crossing the sky to become ‘anticrepuscular’ appear by perspective to converge there. Ground and mountain shadows do the same.

It is the centre of primary and secondary rainbows. Some rarer bows circle different hubs. Fogbows centre there as does the multi-ringed glory.

It is a focus for ice halos, Parry antisolar, the diffuse arcs and a sharp subparhelic circle all cross it.

It is the place of glows both real and perceived. Of the heiligenschein in dew wetted grass and the shadow free spot of the ‘dry’ opposition effect.