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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)
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Hurricane Charley
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)
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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)
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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)
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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)
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Progress undocking
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)
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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)
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Proton preview
This narrated animation profiles the mission of a Proton rocket launching the Amazonas communications satellite. (2min 27sec file)
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Rocket rollout
The fully assembled Proton rocket is rolled to launch pad for its flight to place the Amazonas spacecraft into orbit. (41sec file)
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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)
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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)
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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.


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.
 
"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."

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 cluster.

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.

Ares 1-X Patch
The official embroidered patch for the Ares 1-X rocket test flight, is available for purchase.
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Apollo Collage
This beautiful one piece set features the Apollo program emblem surrounded by the individual mission logos.
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Expedition 21
The official embroidered patch for the International Space Station Expedition 21 crew is now available from our stores.
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Hubble Patch
The official embroidered patch for mission STS-125, the space shuttle's last planned service call to the Hubble Space Telescope, is available for purchase.
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