This image was taken on August 4, 2013, in Caithness, 

Scotland, and it captures an extremely rare spectacle: 

rolling 

noctilucent clouds being illuminated by the beautiful pink and 

purple lights of the aurora borealis. Noctilucent, or night-

shining, clouds are the highest in the atmosphere (about 75 

to 85 km) and are made of tiny ice crystals.