| ISS TOOLBAG: The ISS Toolbag is still orbiting Earth. Just this morning, Eddie Irizarry saw it gliding over Puerto Rico. "Using 9x63 binoculars, I saw the famous object passing between the stars Muphrid and Arcturus in Bootes," reports Irizarry. "It was about 7th to 7.5th magnitude. Slight variations in brightness were evident, suggesting the Toolbag is tumbling as it orbits our planet." Readers, you can catch the Toolbag, too. Check the Simple Satellite Tracker for viewing times. MOTHER-OF-PEARL: Yesterday in Trondheim, Norway, Ivar Marthinusen was watching the sky when "these waves of iridescent color caught my attention." He grabbed a camera and recorded the first nacreous clouds of the season: 
Nacreous clouds are located in the stratosphere between 9 and 16 miles high. Their "mother of pearl" colors come from sunlight striking tiny ice crystals inside the clouds. Very low temperatures near -85o C are required to form the crystals, which is why nacreous clouds are seen mainly during winter over places like Alaska, Iceland and Scandinavia. These clouds are supposed to be rare, yet earlier this year Scandinavians witnessed a veritable "nacreous storm." For more than a week in January 2008, hardly a night went by without someone spotting mother-of-pearl colors in the sky. No one knows what caused the abundance or if it could happen again. One thing is certain: Northern sky watchers should be alert for more. The best time to look is during the twilight hours before dawn or after sunset. SMILE IN THE SKY: Monday, Dec. 15th, was a cold day in Big Sky, Montana. At sunrise the thermometer said -29 F and the air was filled with crystals of ice. It was the perfect moment for a circumzenithal arc: 
"I've worked here at Big Sky ski resort for five winters and this is the first time I've seen one," says photographer Patrick Daigle. "It was a beauty! My co-worker Vicky made the photo possible by blocking the sun behind her." The circumzenithal arc, a.k.a. "smile in the sky", is widely held to be the most beautiful of all ice halos. It appears almost straight overhead when the sun is hanging low and shining through plate-shaped ice crystals--the same crystals that make sundogs. Indeed, Daigle witnessed a brilliant sundog below the arc. Vicky saw it, too. more images: from Mohammad Soltanolkottabi of Esfahan, Iran; from Chris Haws of Faribault, Minnesota; from Theresa Kavouras of Lakeville, Minnesota; from Tom Zerucha of Owatonna, Minnesota; from Lars Michael of Minneapolis, Minnesota; from Bob Johnson of Saskatoon, Saskatchewan
Dec. 2008 Aurora Gallery
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