Noctilucent clouds low on northern horizon, amid midnight twilight of summer solstice, June 28, 2011. Big Dipper and Polaris in upper half of frame. Taken with Canon 7D and 16-35mm Canon zoom lens at 24mm for 8 seconds at f/3.5 and ISO 400
Astronomy author and photographer Alan Dyer presents amazing sky sights
The Amazing Sky 