CRESCENT MOON JOINS THE GREAT CONJUNCTION: When the sun goes down tonight, step outside and look southwest. An exquisitely slender crescent Moon is approaching Jupiter and Saturn on the eve of their Great Conjunction. They form a must-see trio on Dec. 16th and 17th, followed by the Great Conjunction itself on Dec. 21st. No telescope is required! Sky maps: Dec. 16, 17; Dec. 21. Tips: How to Photograph the Conjunction.
DIAMOND DUST SKI HALOS: Ski resorts are one of the best places to see sun halos--rings and pillars of light that surround the sun when ice crystals fill the air. David Smoyer was skiing at the Northstar Terrain Park in Truckee, CA, on Dec. 14th when he saw these specimens:
"It was a chilly morning, and the air was glittering\," says Smoyer. "A huge complex of halos was visible all around the sun."
Smoyer's display was caused by a special type of jewel-like crystal called called "diamond dust." Snow-making machines are very good at making diamond dust and, in fact, "snow-making machines were active in the area," says Smoyer. Some of the individual crystals can be seen in this close-up.
"Ski slopes can unintentionally decorate the sky for us," says atmospheric optics expert Les Cowley. "Their halos can be finer even than the natural ones that halo experts once traveled to the South Pole to research. In David Smoyer's photos a 22° halo circles the sun. At its top are a tangent arc and a rare Parry arc. Further out is a supralateral arc or a rarer 46° halo. It is often hard to tell which!"
All these forms were sculpted from sunlight by diamond dust. If you find yourself skiing and the air begins to glitter, look up at the sun. What you see could make your day.
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All items come with a greeting card showing the gifts in flight, and telling the story of their journey to the edge of space and back again. Don't forget to enter coupon code "SPACESANTA" at checkout for a 10% holiday discount!
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