In this photo, a brilliant Iridium flare blazes in the sky high above the henge.

Iridium flares are caused by particular communication satellites that have large, mirror-like antennas that sometimes reflect sunlight directly onto the Earth below. If the angles are just right, the reflected sunlight can be very bright — in this case, it was magnitude -8 — many times brighter than the brightest stars. The positions of Iridium satellites are precisely known, so it's possible to predict when and where a flare will be seen.

The flare is in between the constellations Draco and Hercules, and the bright star between the flare and the henge is zero magnitude Vega.