SOLAR WIND, INCOMING: A hole in the sun's atmosphere is facing Earth and spraying a stream of solar wind in our direction. Estimated time of arrival: Dec. 18-19. Geomagnetic storms are not expected. However, Arctic sky watchers should be alert for a brightening of auroras when the gaseous material arrives. Aurora alerts: SMS Text.
GREEN FLASH, BLUE FLASH: Green flashes at sunset are rare. Indeed, they were once thought mythological. Blue flashes are rarer still. This evening, Maximilian Teodorescu of Magurele, Romania, saw them both in a single sunset:
"I photographed this superb sunset from the roof of my work place," says Teodorescu. "There was a small blue flash and multiple green flashes, followed by a very deformed sun."
Green flashes are formed when the prismatic action of the atmosphere splits the setting sun into basic R-G-B colors. Temperature inversions create a mirage, magnifying the green into an eye-catching flash.
Blues flashes are formed in the same way, but they are generally harder to see than green flashes, because blue flashes blend into the surrounding blue sky. An exceptionally strong mirage, however, can cause the blue flash to emerge.
Says Teodorescu, "It was a great way to end the day."
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CHRISTMAS GIFTS FROM THE EDGE OF SPACE: So far in 2019, the students of Earth to Sky Calculus have launched 41 space weather balloons to the stratosphere, measuring cosmic rays over 2 continents and 6 different US states. You can help them pay their helium bill by purchasing a Christmas gift from the edge of space:
Every item in the Earth to Sky Store has flown to the stratosphere alongside an array of cosmic ray sensors. Carried aloft by giant helium balloons, these unique gifts travel 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.
Don't forget to enter coupon code "XMASRAYS" at checkout for a 10% holiday discount.
Far Out Gifts: Earth to Sky Store
All sales support hands-on STEM education
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