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GEMINID METEOR SHOWER--THIS WEEK! The annual Geminid Meteor Shower is set to peak on Dec. 13 and 14, 2012. The display, which is caused by an unusual 'rock comet,' could produce more than 100 meteors per hour during the dark hours before dawn this Thursday and Friday. [video] [meteor radar]
ASTEROID FLYBY: Newly-discovered asteroid 2012 XE54 is flying through the Earth-Moon system today approximately 230 thousand km (0.6 LD) from Earth. The space rock is about 36 meters wide, a little smaller than the Tunguska impactor that leveled 800 square miles of Siberian forest in 1908. Using a remote-controlled telescope in New Mexico, astronomers Ernesto Guido and Nick Howes photographed 2012 XE54 streaking among the stars on Dec. 11th:
Guido and Howes dedicate this image to the memory of their longtime friend and colleague Giovanni Sostero.
This asteroid will not hit Earth, but it is close enough, and thus bright enough, for amateur astronomers to track using backyard telescopes. When Guido and Howes photographed it this morning, it was shining at magnitude +13.
Astronomers monitoring the asteroid might have noticed an unusual eclipse during the early hours of Dec. 11th. According to calculations made by P. Tricarico, 2012 XE54 "will likely cross the Earth's shadow, causing a partial eclipse of the asteroid a few hours before reaching its minimum distance with the Earth. Asteroids eclipsing during an Earth flyby are relatively rare, with the first known case of asteroid 2008 TC3 which was totally eclipsed just one hour before entering Earth's atmosphere over Sudan in 2008, and asteroid 2012 KT42 experiencing both an eclipse and a transit during the same Earth flyby in 2012."
Stay tuned for updates.
ARCTIC LIGHTS: There was no geomagnetic storm last night, but around the Arctic Circle a geomagnetic storm is not required to produce auroras. Last night, photographer Mike Theiss was traveling along the Dempster Highway just north of Eagle Plains, Canada, when the sky erupted in color. The sign in the foreground marks the latitude of the Arctic Circle:
"It was insane," he says. "Lights danced all over the sky for 3 hours! I've never seen anything like it."
Theiss was located beneath Earth's auroral oval, a doughnut of light circling the North Pole where auroras sputter on and off even when geomagnetic storms are at low ebb. Displays like this could occur on any night of northern winter. Such auroras are all we can expect for the next few days as NOAA forecasters estimate a mere 5% chance of geomagnetic storms. Aurora alerts: text, voice.
Realtime Aurora Photo Gallery
COLORFUL STRATOSPHERIC CLOUDS OVER EUROPE: When the sun set over the UK on Dec. 9th, sky watchers were stunned by an unexpected apparition of super-colorful stratospheric clouds. "They were amazing to see and a dream come true to photograph," reports Lesley Jennings of Fraserburgh, Aberdeenshire, Scotland. "There were all sorts of colors. I've never see the like before!" added Rachael Taylor also from Aberdeenshire. Nigel Feilden photographed this specimen from Inverurie, Scotland:
"These are nacreous clouds," explains atmospheric optics expert Les Cowley. "Of all Earth's clouds they are most spectacular, and a very rare treat for skywatchers."
"For up to an hour after sunset or before dawn they glow like eerie electric discharges or gas jets in the darkening sky, their filmy shapes slowly curling and uncurling with intense shifting colors. They are composed of tiny ice crystals more than twice as high as ordinary clouds, 9-16 miles up, in the stratosphere and form at temperatures of minus 85 Celsius and below. The crystals are all of similar size and they diffract the high altitude sunlight to make the colours."
"Search for nacreous clouds at high latitudes (e.g., Scotland, Scandinavia, Iceland, Northern US) in winter and preferably downwind of mountains," Cowley advises. "They like stormy weather that perhaps creates gravity waves to loft the necessary moisture to make them upwards across the tropopause into the stratosphere. Once seen they are never forgotten!"
Realtime Nacreous Cloud Photo Gallery
Realtime Space Weather Photo Gallery
Realtime Noctilucent Cloud Photo Gallery
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