Noctilucent Waves Over Orsta, Norway
August 25, 2013
Photographer: Geir T. Oye; Geir's Web site
Summary Authors: Geir T. Oye; Jim Foster
This impressive display of noctilucent clouds (NLC) resembling white caps in an agitated sea was visible over Orsta, Norway in the early hours of July 25, 2013. Many beautiful cloud structures colored in electric blue-white stretched over the Nordic summer sky -- still quite bright even at 1:00 a.m. Noctilucent clouds, also called night shining or polar mesospheric clouds, form approximately 30 to 55 mi (50 to 87 km) above the Earth’s surface. They take shape when water vapor, the source of which is uncertain, condenses around small particles that are likely of meteoric origin. They’re typically only observed during the summer months when the Sun is between 6 and 16 degrees below the horizon.
Photo details: Canon 500D camera; Sigma 70-300 mm lens; ISO 400; 0.8 sec. exposure; tripod used.