Noctilucent Clouds Above Hungary and Estonia

August 18, 2014

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Photographers: Top - Rafael Schmall; Rafael's Web site / Bottom - Ardo Noormets
Summary Authors: Rafael Schmall; Ardo Noormets

The photos above show noctilucent clouds (NLC) observed from Hungary (top) and Estonia (bottom) in July of 2014. These intensely shining clouds can, on occasion, be seen during the summer season from mid to high altitudes; from mid-latitudes look close to the western horizon well after sunset. Noctilucent clouds are composed of water ice, though the source of the water at the altitudes they form (50 mi or 80 km above the surface) is uncertain. Since they occur so high in the atmosphere, they reflect the Sun's light hours after local sunset -- or before sunrise. They're often mistaken for cirrus but form much higher. Click here to see an animation of the Hungary noctilucent clouds. Hungary photo taken on July 4, 2014; Estonia photo taken on July 24, 2014.

Photo details: Top - Camera Model: Canon EOS 6D; Lens: EF28-105mm f/3.5-4.5 USM; Focal Length: 28mm; Aperture: f/8.0; Exposure Time: 8.000 s; ISO equiv: 6400; Software: Adobe Photoshop CS6 (Windows). Bottom - Camera Model: Canon EOS 300D DIGITAL; Lens: 18.0-55.0 mm; Focal Length: 22.0mm; Aperture: f/5.6; Exposure Time: 20.000 s; ISO equiv: 200; Software: Adobe Photoshop Lightroom 3.3.