|
TRIPLE FLYBYS:
Space shuttle Endeavour has undocked from the International Space
Station in preparation for a July 31st return to Earth. Meanwhile,
a Russian supply ship, the Progress 34, is approaching the ISS.
This sets the stage for a rare set of triple flybys. People who
see the space station in the night sky tonight could witness three
spaceships (two bright and one dim) in triangular formation. Check
the Simple Satellite Tracker to find out when
to look.
SPACE STATION SILHOUETTE:
It happened in a split second. On July 26th,
the International Space Station (ISS) flew in front of the sun over
Orleans, France, where astrophotographer Thierry
Legault was waiting. He couldn't see the 0.8s transit with the
unaided eye, but his telescope and digital camera captured this
image:
Photo details: Canon
5D MkII, Takahashi TOA-150 refractor, Herschel prism, 1/8000s
"The silhouette shows space shuttle Endeavour docked to the
ISS," he says. "The shuttle's payload bay arm is visible,
too."
Legault has taken many
pictures
of spaceships passing in front of the sun. When he stands beside
the telescope at the moment of transit, listening to the camera
click, there is no assurance of a good shot. "I never know
if the ship will be visible or not, or if the seeing will give good
or bad images. The discovery of the silhouette on the computer screen
later is the moment I prefer and is a great pleasure."
The ISS will be transiting the French sun again, perhaps several
times, in the weeks ahead, says Legault. Stay tuned for snapshots.
JUPITER'S IMPACT CLOUD
EXPANDS: Jupiter's impact cloud is expanding.
On July 19th, when it was discovered
by amateur astronomer Anthony Wesley, the dark mark near Jupiter's
south pole was barely visible in backyard telescopes. Five days
later Wesley photographed the impact cloud again and found that
it had approximately tripled in size:
High-resolution
images from the Hubble Space Telescope reveal what's happening:
turbulence and jet streams in Jupiter's atmosphere are causing the
cloud to spread out. The vast impact site is now tens of thousands
of times wider than the 100m-class comet or asteroid that created
it.
The expansion of the cloud makes it easier than ever to see through
a backyard telescope: sky
map. The cloud is located near Jupiter's System II longitude
210°. For the predicted times when it will cross the planet's central
meridian, add 2 hours and 6 minutes to Sky and Telescope's predicted
transit times for Jupiter's Great Red Spot.
more images: from
Mike Hood of Kathleen, Georgia; from
Didier Favre of Brétigny-sur-orge, France; from
Enzo De Bernardini of Martínez, Buenos Aires, Argentina; from
Sadegh Ghomizadeh of Iran Tehran; from
David Kolb of Lawrence, Kansas;
July
2009 Aurora Gallery
[previous Julys: 2008,
2007, 2006,
2005, 2004,
2003]
2009
Noctilucent Photo Gallery
[previous years: 2008,
2007, 2006,
2005, 2004,
2003]
July
22nd Eclipse Gallery
[previous eclipses: Jan
26, 2009; Aug.
1, 2008; Mar. 19,
2007]
Explore
the Sunspot Cycle
|
