Anticrepuscular rays (w-548-02)

In gallery: Photos of the month (2003)
Related photos: Atmospheric optics Twilight phenomena Anticrepuscular rays

These remarkable anticrepuscular rays were visible over New Mexico (USA) on October 11 just after sunset. The rays are just solar rays, but appear opposite the sun when it is just below the horizon. The rays are cast by distant clouds that are usually below the horizon and not visible, on small aerosols (like dust particles). The rays span the sky at high altitude and can extend for hundreds of miles. The dark horizontal band is the shadow of Earth being cast on the atmosphere (the so-called twilight wedge).

Photo taken with Nikon FE, 20mm wide-angle lens at f/8 on Fuji Provia 100F film.