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MORNING PLANETS:
If you wake up early on Sunday morning,
May 17th, look out the window. Jupiter and the Moon are having a
close encounter in the dawn sky. There's nothing astronomically
significant about the encounter; it's just a nice way to begin the
day. [sky map]
SPACESHIPS IN THE
SUN: Award winning astrophotographer Thierry
Legault wanted to image the Hubble Space Telescope and space
shuttle Atlantis traveling together around Earth. But how? The pair
wouldn't fly over his hometown in France during the ongoing servicing
mission. To catch the rare meeting of spaceships, he decided to
do some traveling of his own all the way to Florida. On May 12th,
from a location near the Kennedy Space Center, he pointed his solar-filtered
telescope at the sun and voilà!--there was Atlantis:
The space shuttle's silhouette was beautifully outlined by solar
fire as Atlantis passed over central Florida.
A day later, he tried again, and this time Hubble joined the show:
"I took this
picture of Atlantis and the space telescope transiting the sun
together on May 13th. It was just before the shuttle reached out
with its robotic arm to grapple Hubble," says Legault. "The
two spaceships were at an altitude of 600 km and they zipped across
the sun in only 0.8 seconds." He captured the split-second
transit using a Takahashi 5-inch refracting telescope and a Canon
5D Mark II digital camera.
Hubble is now safely stowed inside the shuttle's cargo bay where
astronauts are conducting a series of five spacewalks to repair
and upgrade the telescope. So far they have installed a new camera,
replaced gyros, batteries and a failed computer. These upgrades
and others are expected to extend Hubble's life until 2014. [more]
STRANGE POND SHADOWS:
On May 12th, Maurice Gavin
bent over a turbid pond at the Minsmere bird reserve in Suffolk,
UK, and saw something that surprised him. "There were radial
shadows coming out of my head," he says. Here is a snapshot:
Gavin also made a video of the multi-colored ripples: click
here.
Atmospheric (and underwater) optics expert Les Cowley explains
the phenomenon: "The light and dark streaks radiating from
Gavin’s head are a water
aureole. It is a perspective effect rather like anti-crepuscular
rays. Waves on the surface focus the sun into parallel cones
of light pointing downwards through the water. The aureole, seen
when the water is slightly cloudy, is your view of the cones apparently
converging on the point opposite the sun where your shadow is also
situated."
"Gavin’s colored
shadows are another cloudy water effect. Small particles in
water scatter sunlight like the air molecules that make the sky
blue. When we see the particles side on to the light against the
dark shadow background they look blue. But scattering blue light
leaves sunlight reddened. These remaining 'sunset rays' make other
shadow edges appear orange-red."
"Watch water carefully, it has as almost as many colorful
effects as the sky!"
more images: from
Tom Soetaert of Lawrence, Kansas
April
2009 Aurora Gallery
[previous Aprils: 2008,
2007, 2006,
2005, 2004,
2003, 2002]
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the Sunspot Cycle
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