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DEEP QUIET:
Today, the sun is entering its 13th consecutive day without
sunspots. Just a few years ago, such a stretch of blank suns
would have been unthinkable. Now it's routine. So far this
year, the sun has been spotless 79% of the time, topping the
73% mark recorded in 2008. Long after many forecasters thought
solar minimum would be finished, the quiet is not only continuing,
but actually deepening. Are sunspots gone for good? Researchers
discuss the question in an
article from Science@NASA.
NETHERLANDS FIREBALL:
A fireball as bright as the full Moon startled
observers in the Netherlands yesterday when it raced across
the evening twilight sky. A lucky shot by photographer Jan
de Vries at approximately 1658 UT caught the meteor in mid-flight:
"It was spectacular," says eyewitness Dominic Doyle
of the European Space Agency in Noordwijk. "I estimate
its magnitude to be about -12," adds amateur astronomer
Koen Miskotte, who saw it from the small village of Ermelo.
Various observers report it breaking apart into as many as
a half-dozen pieces, followed by sonic booms, low rumbles
and shaking windows. A Royal Dutch Meteorology Institute listening
post detected strong infrasound (low-frequency sound)
waves, apparently confirming a high-altitude breakup event:
data.
more images: from
Robert Mikaelyan of Groningen, The Netherlands
NORTHERN LIGHTS:
A minor solar wind stream hit Earth's magnetic field on Oct.
11th, sparking green auroras around the Arctic Circle. Aleksander
Chernucho photographed the display from Russia's Kola Peninsula
not far from the border of Finland:
"I used a Nikon
D700 for this 10 second exposure," he says.
More auroras could appear on Oct. 15th when
another solar wind stream is expected to reach Earth. Arctic
sky watchers should be
alert for green lights in the sky.
more images: from
M-P Markkanen of Kuusamo, Finland
Sept.
2009 Aurora Gallery
[previous Septembers: 2008, 2007, 2006, 2005, 2004, 2002, 2001]
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