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URSID METEORS:
Earth is passing through a stream of debris from comet 8P/Tuttle
and this is causing the annual Ursid meteor shower. Forecasters
expect the Ursids to peak on Dec. 22nd with 8 to 10 meteors per
hour flying out of the constellation Ursa Minor (the Little Dipper).
The display is usually mild, but outbursts of Ursids occasionally
surprise observers with rates many times normal.
Watching these northern meteors can be a chilling experience, so
why not stay inside and listen to them instead? Spaceweather.com
is broadcasting live audio from the Air Force Space Surveillance
Radar in Texas. When a meteor passes over the radar--"ping"--there
is an echo. Give
it a try; feedback is welcomed.
MIDNIGHT VISITATION:
In a remote area of New Mexico, amateur
astronomer Thomas Ashcraft
operates an all-sky camera for nightly monitoring of meteors and
fireballs. "The other night I caught a big one," he says.
Click on the image to play the movie:
"An owl descended from the sky and landed on
the clear dome of my fireball camera," explains Ashcraft. "It
stayed for a few minutes and then flew away." This visitor
was probably a Western Screech-Owl or a Great Horned Owl, two varieties
common to New Mexico. Ornithologists may be able to pinpoint the
species; the owl glances down during the
video for a revealing self-portrait.
Bright meteors turn out to be far more common than
visiting owls. Browse Ashcraft's fireball
catalog for a typical night's catch.
SUNDOG ALERT:
Winter weather storming across the northern USA and Canada is filling
the air with ice
and filling the sky with ice
haloes. "These sundogs appeared during our ground blizzard
yesterday," reports Steve
Yezek of Grafton, Iowa:
"It was very cold outside with temperatures below
zero, and there were strong, gusting winds," he says.
Similar conditions in Omaha, Nebraska, produced a
double
halo around the sun. In addition, onlooker Tyler Burg witnessed
"sundogs,
a segment of a supralateral
arc, and an upper
tangent arc that persisted for the better half of 4 hours. It
was a nice display."
Readers, if it's cold where you live, bundle up, go
outside, and look at the sky. The sundogs are barking!
more images: from
Alain Turgeon in the La Vérendrye wildlife reserve of northern
Quebec; from
Sally J Smith of Wadhams, New York; from
Mark Poe of Aberdeen, South Dakota;
Dec.
2008 Aurora Gallery
[Previous Decembers: 2007,
2006, 2005,
2001, 2000]
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