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2006 July 24
The International Space Station on the Horizon Credit:
STS-121 Crew
,
Expedition 13 Crew
,
NASA
Explanation: This was home. Last week, theSTS-121 crew of the Space Shuttle Discovery undocked from theInternational Space Station (ISS) and returned to Earth. As the shuttle departed the space station, they took theabove image
. Visible on theISS
are numerous modules, trusses, and long wing-like solar panels
. The space shuttle crew spent over 12 days calling the space station home. The
shuttle crew
resupplied the space station and prepared it for future assembly. TheISS's crew of two was expanded to three by theshuttle visit, and now includesone Russian,
one American, and one European.
2006 July 23
The Belt of Venus over the Valley of the Moon
Credit & Copyright:
Christine Churchill
Explanation: Although you've surely seen it, you might not have noticed it. During a cloudlesstwilight, just beforesunrise
or aftersunset, part of the atmosphere above the horizon appears slightly off-color, slightly pink. Called the
Belt of Venus, this off-color band between the darkeclipsed sky and the blue sky can be seen in nearly every direction including that opposite the Sun. Straight above, blue sky
is normal sunlight reflecting off the atmosphere. In the Belt of Venus
, however, the atmosphere reflects light from the setting (or rising) Sun which appears more red. The Belt of Venus can be seen from any location with a clear horizon. Pictured above, the Belt of Venus was photographed above morning fog in the
Valley of the Moon, a famous wine-producing region in northern California, USA
. The belt is frequently
caught
by
accident
in
other
photographs.
2006 July 21
Strangers on Mars
Credit:
Mars Exploration Rover Mission
,
Cornell
,
JPL
,
NASA
Explanation:
This view
from the winter station of Mars Exploration Rover Spirit, looks across the rock strewn landscape of
Gusev Crater
. The dark boulders and distant hills are characteristic of the region, but the two light colored rocks in the foreground of this cropped image are -
like Spirit
itself - most probably strangers to the Red Planet, believed
to be iron
meteorites
. Informally named for sites
in Antarctica
they have been dubbed \"Zhong Shan\" and \"Allan Hills.\" Zhong Shan is the Antarctic base of the People's Republic of China. Allan Hills is the icy location where many Martian meteorites
have been found
on planet Earth, including the controversial
ALH84001
, suggested to contain evidence for fossilized Martian microbial life.
Tomorrow's picture:
wonderful weekend
2006 July 20
Constellation Construction
Credit & Copyright: Jerry Lodriguss (
Catching the Light
)
Explanation: This
lovely twilight scene
, recorded last April, finds a
young
crescent Moon low in the west at sunset. Above it,
stars shine
in the darkening sky but they too are soon to drop below the western horizon. These stars and constellations are prominent in the northern hemisphere
winter sky
and as the season
changes
, slowly give way to the
stars of summer
. Sliding your mouse over the picture will detail the
constellations
and stars in view, including Orion, Gemini,
Auriga
, Perseus, and the Hyades and Pleiades star clusters.
2006 July 19
Reflections on Planet Earth
Credit: Michael Fossum,
STS-121 Mission
,
NASA
Explanation: Catching sight of
your reflection
in a store window or shiny hubcap can be entertaining and occasionally even inspire a thoughtful moment. So consider
this reflective view
from 300 kilometers
above planet Earth
. The picture is actually a
self-portrait
taken by astronaut Michael Fossum on July 8 during a space walk or extravehicular activity while the
Discovery
orbiter was docked with the International
Space Station
. Turning his camera to snap a picture of his own helmet visor, he also recorded the reflection of his fellow
mission
specialist, Piers Sellers, near picture center and one of the space station's gold-tinted solar power arrays arcing across the top. Of course, the horizon of
our fair planet
lies in background.
2006 July 17
Venus Express Arrives at Venus
Credit:
ESA
/
MPS
,
Katlenburg-Lindau
,
Germany
Explanation: Humanity now has a spacecraft orbiting Venus. The robotic
Venus Express spacecraft
launched by the
European Space Agency
in 2005 November arrived at
Venus
in 2006 April. Venus Express is now orbiting Earth's sister planet and returning pictures.
Pictured above
is a false-color, time-lapse movie in
ultraviolet light
captured by the Venus Express spacecraft as it flew over
Venus
' northern hemisphere in late May.
Venus Express
is scheduled to orbit
Venus
for three years and collect data that might help in answering questions that include why Venus continually generates
hurricane-force
winds, why Venus became
so hot
in the past, and if there is any current volcanic activity on
Venus
. It is hoped that a better understanding of
Venus's hot
and inhospitable climate will help humanity better understand
Earth's climate
as well.
2006 July 16
The Galactic Center in Infrared
Credit:
2MASS Project
,
UMass
,
IPAC/Caltech
,
NSF
,
NASA
Explanation: The center of our Galaxy is a busy place. In
visible light
, much of the
Galactic Center
is obscured by opaque
dust
. In
infrared light
, however, dust glows more and obscures less, allowing nearly one million stars to be recorded in the
above photograph
. The
Galactic Center
itself appears
on the right and is located about 30,000
light years
away towards the constellation of
Sagittarius
. The
Galactic Plane
of our
Milky Way Galaxy
, the plane in which the
Sun
orbits, is identifiable by the
dark diagonal dust lane
. The absorbing
dust
grains are created in the atmospheres of cool
red-giant stars
and grow in
molecular cloud
s. The region directly surrounding the
Galactic Center
glows brightly in
radio
and
high-energy radiation
, and is thought to house a large
black hole
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发表于 2006-7-24 12:51:35
发表于 2006-9-12 09:21:44
