Lunar Corona over Cochem Castle . ... Credit Copyright: Babak Tafreshi ( TWAN ) Explanation: This bat-like apparition does not shine on clouds passing over Gotham city . Instead, the cloud bank in silhouette against a colorful lunar corona was spotted on the evening of May 18 over Cochem, Germany from the banks of the river Mossele. The lunar corona is formed as bright moonlight is diffracted by water droplets in thin clouds drifting in front of the lunar disk. ... NASA Official: Jay Norris. ...