Photo of atmospheric phenomenon during Brno sunset NASA's Astronomy Picture of Day

NASA's Astronomy Picture of the Day on Friday was of anticrepuscular rays seen during a sunset in Brno, taken by Czech astronomer Pavel Gabzdyl. The picture was taken on 11 July during the city's annual Planet Festival in the park below the Brno Observatory and Planetarium.

Anticrepuscular rays are subtle bands of light and shadow cast across the sky, formed as a large cloud bank near the western horizon cast long shadows through the atmosphere at sunset. Due to the camera's perspective, the rays seem to converge toward the opposite horizon at a point just above a 14th-century hilltop castle near Brno.