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SEVEN SISTERS AND
THE SUN: You can't see it, but the Solar
and Heliospheric Observatory (SOHO) can. A
conjunction is underway between the Pleiades and the sun. Using
its coronagraph to block the sun's glare, SOHO is monitoring the
heavenly encounter. Click
here for a ringside seat.
JUST HANGIN' AROUND:
Regard the pair of photos below. Now cross
your eyes and you will see what it is like to work on the Hubble
Space Telescope:
Click to view a larger
image and alternate left-right pairs
The stereo pair, prepared by graphic artist Patrick Vantuyne of
Belgium, shows spacewalker Andrew Feustal "just hangin' around"
shuttle Atlantis' cargo bay on May 18th. Feustal had paused for
fellow spacewalker John Grunsfeld to take his picture during a grueling
7 hour 2 minute spacewalk that put the finishing touches on NASA's
masterpiece STS-125 Hubble
repair mission. Thanks to their efforts, Hubble is back in orbit
and working again, better than ever. Meanwhile, the crew of Atlantis
is scheduled to land in Florida on Friday, May 22nd, at 10:00 am
EDT, although bad weather threatens to delay their return. Stay
tuned for updates.
GREEN FLASH:
Green flashes
from the sun are brief and elusive. You can miss one simply by blinking.
So imagine the surprise of Lance
B. of the Cayman islands on May 17th when he watched a flash
endure for two ... long ... seconds. "I had enough time to
take this picture," he says:
The green spot on the horizon is the flash showing
itself during the very last seconds of sunset.
Green flashes happen when the normally mild
refraction of Earth's atmosphere is amplified
by a mirage. "The mirage occurs when there is warm air immediately
over the ocean and the air temperature gradient changes rapidly
with height," says atmospheric optics expert Les Cowley. "For
the flash to be visible the warm air layers must be below you."
"The air was still and very hot; I knew the conditions
were favorable," says Lance. "This was the longest green
flash I've ever seen!"
more images: from
Paul Edmondson of Point Reyes, CA; from
Wolfgang Ott of Stuttgart, Germany; from
James Helmericks of Colville River Delta, Northern Alaska;
April
2009 Aurora Gallery
[previous Aprils: 2008,
2007, 2006,
2005, 2004,
2003, 2002]
Explore
the Sunspot Cycle
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