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Ship docks to station
The Russian Progress 15P resupply ship makes a fully automated rendezvous and docking with the International Space Station. An external camera on the craft provides this view of the final approach to the aft port of the Zvezda service module. (3min 49sec file)
A camera aboard the International Space Station captured this stunning view of the strengthening Hurricane Charley on the morning of August 12. (1min 32sec file)
Tropical Storm Bonnie
As Tropical Storm Bonnie comes ashore in the Florida panhandle on the morning of August 12, the International Space Station provides this view as it the orbiting outpost flies overhead. (1min 40sec file)
Reentry seen from space
An incredibly rare sight was captured by the International Space Station cameras when the discarded Progress 14P supply ship reentered Earth's atmosphere. The craft burned up during the fiery plunge, which is visible as a long streak below the station. (3min 49sec file)
Earth as backdrop
Spectacular video of the departing Progress 14P cargo ship against the Earth backdrop is captured by the station's crew. (1min 34sec file)
The Russian Progress 14P cargo ship undocks from the International Space Station after delivering its load of supplies and fuel to the orbiting outpost. A camera mounted on the craft's nose provides this view of the Progress departing the aft port of the Zvezda service module. (2min 15sec file)
Proton lofts Amazonas
A Russian Proton M rocket launches from Baikonur Cosmodrome carrying the Amazonas communications satellite that will serve the Americas and Europe. (2min 25sec file)
This narrated animation profiles the mission of a Proton rocket launching the Amazonas communications satellite. (2min 27sec file)
The fully assembled Proton rocket is rolled to launch pad for its flight to place the Amazonas spacecraft into orbit. (41sec file)
MESSENGER lifts off
The Boeing Delta 2-Heavy rocket launches at 2:16 a.m. EDT carrying the NASA's MESSENGER space probe from Cape Canaveral, Florida. (5min 23sec file)
Cocoa Beach view
The Cocoa Beach tracking camera site captured this beautiful view of the launch and separation of the ground-ignited solid rocket boosters. (1min 31sec file)
Next station crew
Expedition 10 Commander and NASA ISS Science Officer Leroy Chiao and Soyuz Commander and Flight Engineer Salizhan Sharipov discuss their planned six-month mission on the space station. (11min 23sec file)
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Chandra catches early phase of cosmic assembly
CHANDRA X-RAY CENTER NEWS RELEASE
Posted: August 14, 2004
A NASA Chandra X-ray Observatory image has revealed a complex of several intergalactic hot gas clouds in the process of merging. The superb Chandra spatial resolution made it possible to distinguish individual galaxies from the massive clouds of hot gas. One of the clouds, which envelopes hundreds of galaxies, has an extraordinarily low concentration of iron atoms, indicating that it is in the very early stages of cluster evolution.
"We may be seeing hot intergalactic gas in a relatively pristine state
before it has been polluted by gas from galaxies," said Q. Daniel Wang
of the University of Massachusetts in Amherst , and lead author on an
upcoming Astrophysical Journal article describing the study. "This
discovery should provide valuable insight into how the most massive
structures in the universe are assembled."
Chandra's image of the galaxy cluster Abell 2125 reveals a complex of several massive multimillion-degree-Celsius gas clouds in the process of merging. Ten of the point-like sources are associated with galaxies in the cluster, and the rest are probably distant background galaxies. The bright gas cloud on the upper left is the core of the cluster and envelopes hundreds of galaxies. Credit: NASA/CXC/UMass/Q.D.Wang et al.
The complex, known as Abell 2125, is about 3 billion light years from
Earth and is seen at a time about 11 billion years after the Big Bang.
This is a period when astronomers believe many galaxy clusters are
formed. Chandra's Abell 2125 image shows several huge elongated clouds
of multimillion-degree-gas coming together from different directions.
These hot gas clouds, each of which contains hundreds of galaxies,
appear to be in the process of merging to form a single massive galaxy
Chandra, Hubble Space Telescope, and Very Large Array radio telescope
data show that several galaxies in the Abell 2125 core cluster are being
stripped of their gas as they fall through surrounding high-pressure hot
gas. This stripping process has enriched the core cluster's gas in heavy
elements such as iron.
The gas in the pristine cloud, which is still several million light
years away from the core cluster, is conspicuous for its lack of iron
atoms. This anemic cloud must be in a very early evolutionary stage.
The iron atoms produced by supernovas in the embedded galaxies must
still be contained in and around the galaxies, perhaps in grains of dust
not well mixed with the observed X-ray-emitting gas. Over time, as the
cluster merges with the other clusters and the hot gas pressure
increases, the dust grains will be driven from the galaxies, mixed with
the hot gas, and destroyed, liberating the iron atoms.
Building a massive galaxy cluster is a step-by-step enterprise that
takes billions of years. Exactly how long it takes for such a cluster
to form depends on many factors, such as the density of subclusters in
the vicinity, the rate of the expansion of the universe, and the
relative amounts of dark energy and dark matter.
Cluster formation also involves complex interactions between the
galaxies and the hot gas that may determine how large the galaxies in
the cluster can ultimately become. These interactions determine how the
galaxies maintain their gas content, the fuel for star formation. The
observations of Abell 2125 provide a rare glimpse into the early steps
in this process.
Frazer Owen (National Radio Astronomy Observatory) and Michael Ledlow
(Gemini Observatory) are co-authors on the upcoming Astrophysical
Journal paper. Chandra observed Abell 2125 with its Advanced CCD
Imaging Spectrometer on August 24, 2001, for approximately 22 hours.
NASA's Marshall Space Flight Center, Huntsville, Ala., manages the
Chandra program for NASA's Office of Space Science, Washington. Northrop
Grumman of Redondo Beach, Calif., formerly TRW, Inc., was the prime
development contractor for the observatory. The Smithsonian
Astrophysical Observatory controls science and flight operations from
the Chandra X-ray Center in Cambridge, Mass.