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Tuesday, February 11, 2014

Lunar Halo

lune_halo_2014-02-11.jpg

Click image to enlarge.

On the evening of February 11th, 2014 a beautiful 22° halo surrounded the Moon. These halos are caused by light refracted by randomly-oriented hexagonal ice crystals in the atmosphere. Because light of different wavelengths is refracted at different angles, the inner part of the halo appears red and the outer part blue. This was not apparent to the eye, but the camera picked up the colour in this saturation-enhanced image. Thin clouds fill the halo. Above the extremely overexposed Moon is Jupiter. The constellation Orion is visible with Betelgeuse at the inner edge of the ring at about the 2 o'clock position.

The photo was taken with a Nikon D600 digital camera and Nikon 14–28 mm f/2.8 zoom lens at 14 mm. Exposure was 2 seconds at f/2.8 with ISO sensitivity of 400.

Posted at February 11, 2014 21:24