DOOMED SPACECRAFT:
Jules Verne is about to become a fireball.
On Sept. 29th, with NASA airplanes
looking on, the 22-ton European
spacecraft will plunge into Earth's atmosphere over the south
Pacific Ocean. Jules Verne recently spent five months docked to
the space station where it delivered supplies, used its engines
help the station avoid a piece of space junk, and served as an impromptu
bedroom for the ISS crew. Mission accomplished, the doomed spacecraft
is now making its final orbits around Earth. If you'd like to see
it, check the Simple Satellite Tracker for
viewing times.
MICKEY MOUSE EARS:
Ultraviolet photos taken by the Solar and
Heliospheric Observatory (SOHO) reveal the a strange pair of "Mickey
Mouse" ears on the sun. They've been sighted many times in
recent weeks and are especially prominent today:
What are they? Coronal
cavities--regions of low density, high temperature gas contained
by loops of magnetic field. Coronal cavities are where prominences
are born. Indeed, there is a prominence inside the righthand cavity;
look for it in the red image, above, also from SOHO.
There's more to this story. The two ears appear to
be two distinct cavities. In fact, they are one. The actual cavity
is a collosal ring encircling the north pole of the sun. Geometrically,
it is similar to the auroral
ovals of Earth. The two ears are cross-sections of the translucent
ring, distinctly visible because they hang out over the edge of
the solar disk.
The ring-shaped cavity is also known as the sun's
"polar crown" and it spawns some truly
beautiful prominences. The polar crown is easiest to see during
solar minimum when the sun is not cluttered with spots--so now is
the perfect time. Look for the ears in daily
images from SOHO.
SUN PILLAR: When
the sun went down this evening in Frankfurt, Germany, a blood-red
column of light lept up to signal its exit. Horst Templin snapped
this picture using his Nikon
Coolpix 4500:
This is a sun
pillar and it is a sign of ice in the sky. Flat, plate-shaped
ice crystals
fluttering down like leaves from high clouds caught the red rays
of the setting sun and redirected
them into a vertical column of light. Sun pillars may be seen
whenever icy clouds drift across the sunset. Look for your own this
evening!
more images: from
Alan Barrington of Hammerfest, Norway; from
Jon Hayden of Indian Trail Springs, Oregon; from
Marek Nikodem of Kcynia, Poland; from
John Stetson of Sebago Lake, Maine; from
Mike Sessions of Mauna Kea, Hawaii;
Sept.
2008 Aurora Gallery
[Aurora Alerts] [Night
Sky Cameras]
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