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ASTEROID NEAR MISS:
On Nov. 6th at 2132 UT, asteroid 2009
VA barely missed Earth when it flew just 14,000 km above
the planet's surface. That's well inside the "Clarke
Belt" of geosynchronous satellites. If it had hit,
the ~6-meter wide space rock would have disintegrated in the
atmosphere as a spectacular fireball, causing no significant
damage to the ground. 2009 VA was discovered just 15 hours
before closest approach by astronomers working at the Catalina
Sky Survey.
MAGNETIC FILAMENT:
Today, amateur astronomers are monitoring
a picturesque magnetic filament looping around the western
limb of the sun. Jan Timmermans sends this picture from his
backyard observatory in Valkenswaard, The Netherlands:
The portion of the filament seen in front of
the sun looks dark, because it is cooler than the inferno
below. But note how the filament glows in projection against
the black space beyond the limb. The glow comes from plasma
trapped inside the filament--not as bright as the surface
of the sun, but definitely brighter than the void.
"The image clearly shows that the only
difference between a 'dark' filament and a 'bright' prominence
is where they are located: inside or outside the solar disk,"
notes Timmermans. (diagram)
more images: from
Stephen Ames of Hodgenville, Kentucky;
FARSIDE EXPLOSION:
On Nov. 5th, something exploded on the far
side of the sun. The blast hurled a coronal mass ejection
(CME) over the sun's limb, recorded by coronagraphs on the
Solar and Heliospheric Observatory (SOHO). Click on the image
to launch a 14-hour time lapse movie:
The source of the eruption is probably sunspot 1029, which
is transiting the far side of the sun. Last week, when sunspot
1029 was visible from Earth, it quickly grew into the biggest
and most active sunspot of the year, unleashing ten C-class
solar flares in just a few days. Apparently, the action hasn't
stopped. The sun's rotation will turn the sunspot back toward
Earth about a week from now. If the sunspot holds together
that long, we could experience some solar activity. Stay
tuned.
October
Northern Lights Gallery
[previous Octobers: 2008,
2007, 2006,
2004, 2003,
2002, 2001]
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