Polar Mesospheric Clouds in South Pacific Ocean
Polar mesospheric clouds (noctilucent or “night shining” clouds) form between 76 to 85 kilometers (47 to 53 miles) above the Earth’s surface, near the boundary of the mesosphere and thermosphere, a region known as the mesopause. Image © Astronaut William L. Stefanov, Jacobs/ESCG at NASA-JSC.
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Sun Pillar over Sweden
A beautiful Sun Pillar over Sweden. When the air is cold and the Sun is rising or setting, falling ice crystals can reflect sunlight and create an unusual column of light. In the above picture taken last week, a sun-pillar reflects light from a Sun setting over Östersund, Sweden. Image © Göran Strand Used with permission.
A Halo around the Moon in Athens
A halo around the Moon. This fairly common sight occurs when high thin clouds containing millions of millions tiny ice crystals cover much of the sky. Image credit: Anthony Ayiomamitis (TWAN)
Brilliant Sun Pillar over Jenison, Michigan
The photo above showing a breathtaking Sun pillar was captured at sunset near Jenison, Michigan on April 10, 2012. Sun pillars result from the reflection of sunlight off the bottom surfaces (or less frequently, the top surfaces) of plate-shaped ice crystals composing cirrus clouds. Photographer: Kevin Povenz; Kevin’s Flickr Web site
Circumzenithal Arc over Florida Panhandle
The photo above, snapped in Gulf Breeze, Florida on a chilly February afternoon, shows a colorful circumzenithal arc (CZA) and a much less frequently observed (and somewhat dimmer) lateral arc just beneath it. Photographer: Jay Brazel
Lunar Halo, Orion and Grossglockner
This is a 22 degree lunar halo about a waxing, gibbous Moon, the constellation of Orion and a mid-winter landscape in the Fusch Valley of east-central Austria. Photographer: Selina and Patrick Hochleitner; Patrick’s Web site
Lunar halo in Greenland
This lunar halo, photographed in Greenland, where the skies are wonderful. Lunar halos are rare and can be seen anywhere where there’s very thin ice crystals on the air, so they are more usual on the polar regions. Photographer Ed Stockard
Cirrocumulus sky over Missouri
The photo above, captured about an hour before sunset at our home in west-central Missouri, shows a “mackerel sky” composed of cirrocumulus undulatus clouds. Photographers Ramona Miller, Grant Miller
Sundog and bright tail over Trento
The photo above showing a colorful sundog heeling the horizon was taken in Trento, Italy on the afternoon of November 29, 2011. Photographer: Alessandro Zotta
Halo in Tibet
The particularly colorful halo featured above was snapped at Yamdrok Tso Lake, Tibet on October 29, 2011. This is a 22-degree halo — the radius of the inner ring to the Sun. It’s the most frequently observed of the circular halos. Randomly oriented, hexagonal ice crystals in cirrus clouds are responsible for its formation. Photographer Alan Millar
