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ANOTHER
SURPRISE FROM THE SUN: A massive "current
of fire" on the sun has started running at high speed,
surprising researchers and challenging some models of the
solar cycle. Get the full
story from Science@NASA.
NORTHERN
LIGHTS: Statistically speaking, March is
the most geomagnetically active month of the year; October
is a close second. Although the reasons why are not fully
understood, there is no doubt that equinoxes
favor auroras. Just look at the sky this morning over
Tromsø, Norway:
"It was a sudden and stunning outburst
of activity," says photographer Thomas Hagen. "The
auroras were so bright, they turned the water
green."
This could be just the beginning of a really
terrific display on March 16th and 17th. That's when a solar
coronal mass ejection (CME, movie)
is due to hit Earth's magnetic field. NOAA forecasters estimate
a 30% chance of geomagnetic activity and a 5% chance of severe
geomagnetic storms. Sky watchers in Alaska, Canada, Scandinavia,
and northern-tier US states such as Minnesota and Wisconsin
should be alert
for auroras.
UPDATED: March
Northern Lights Gallery
[previous Marches: 2009,
2008, 2007,
2006, 2005,
2004, 2003]
COMET TOAST:
The solar system has one less comet. On March 12th, the Solar
and Heliospheric Observatory (SOHO) watched as a comet plunged
into the sun and disappeared. Fierce solar heating completely
destroyed the icy visitor from the outer solar system. Click
on the image to see the comet's last hours:
The comet was probably a member of the Kreutz
sungrazer family. Named after a 19th century German astronomer
who studied them in detail,Dirk Peeters.Kreutz sungrazers
are fragments from the breakup of a giant comet at least 2000
years ago. Several of these fragments pass by the sun and
disintegrate every day. Most are too small to see but occasionally
a big fragment--like this one--attracts attention.
UPDATE:
Several readers have noticed that the doomed comet was actually
a string of doomed comets, plural. Click
here for a Youtube video posted by Kurt McNamara, and
here for a sequence of labeled diagrams from Dirk Peeters.
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