STRONG GEOMAGNETIC STORM WATCH--CANCELLED: A coronal mass ejection (CME) expected to hit Earth on Dec. 9th either missed or its impact was too weak to notice. Either way, today's strong geomagnetic storm watch is cancelled. A late arrival on Dec. 10th might still cause a minor G1-class storm. CME impact alerts: SMS Text.
LUNAR PARHELIC CIRCLE: This is very rare. On Dec. 3rd, Sheila Wiwchar noticed a gigantic ring of light circling the sky over her home in Kaleida, Manitoba. The full Moon, blazing like a white-hot diamond, sat on one side of the ghostly ring. “I grabbed my camera and rushed outside!” she says.
“I was so excited to see this rare optical phenomenon!” says Wiwchar.
It's called a lunar parhelic circle, formed by moonlight reflecting from the faces of ice crystals. "Our temperature was around –18°C with plenty of ice crystals in the air," notes Wiwchar. Many kinds of reflections (internal, external, single, double, triple and more) are required to form the complete circle. That’s why parhelic circles are uncommon, and lunar parhelic circles are rarer still.
Most parhelic circles appear in broad daylight, with the sun playing the role of "white-hot diamond." In this case, however, the brilliant winter Moon did the trick. December's Cold Moon was a supermoon, one of the brightest of the year.
Observing tip: A parhelic circle always goes completely around the sky--like the ring around a dirty bathtub--maintaining the same altitude as the sun or Moon. If you see a pale arc in one direction, don’t stop there. Spin around and look for the full ring.
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STOCKING STUFFERS FROM THE EDGE OF SPACE: Christmas is coming. Are you looking for a far-out gift? Check out the Earth to Sky Store. It's filled with items that have visited the edge of space onboard cosmic ray research balloons.
These unique gifts have flown above 99.7% of Earth's atmosphere, experiencing space-like blasts of cosmic rays, extreme cold, and a wild ride parachuting back to Earth after the balloon explodes. Even Amazon doesn't carry items this far out.
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