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Shuttle testing
Testing to support the space shuttle return to flight is being performed at NASA's Ames Research Center. This footage shows wind tunnel testing using a shuttle mockup and thermal protection system tests in the arc jet facility. (5min 02sec file)
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History flashback
In this video clip from the archives, a Lockheed Titan 4A rocket blasts off from Cape Canaveral on February 7, 1994 carrying the U.S. Air Force's first Milstar communications satellite. (6min 17sec file)
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Titan 4A rocket
The mobile service tower is retracted to expose the massive Titan 4A-Centaur rocket during the final hours of the countdown in 1994. Aerial video shot from a helicopter shows the booster standing on its Cape launch pad. (3min 06sec file)
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NASA budget
NASA Administrator Sean O'Keefe, in his final press conference appearance, presents the 2006 budget information and answers reporters' questions on Hubble, the exploration plan and shuttle return-to-flight. (86min 37sec file)
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Meet the next ISS crew
Expedition 11 commander Sergei Krikalev, flight engineer John Phillips and Soyuz taxi crewmember Roberto Vittori hold a pre-flight news conference in Houston. Topics included problems with the shuttle safe haven concept. (42min 23sec file)

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Final Atlas 3 launched
The last Lockheed Martin Atlas 3 rocket launches from Complex 36 at Cape Canaveral Air Force Station at 2:41 a.m. EST carrying a classified spy satellite cargo for the U.S. National Reconnaissance Office. This movie follows the mission through ignition of Centaur. (5min 30sec file)
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Atlas 3 onboard
A camera mounted on the Centaur upper stage captured this dramatic footage of the spent first stage separation, deployment of the RL10 engine nozzle extension, the powerplant igniting and the rocket's nose cone falling away during launch.
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Europe's Mars Express sees signs of a 'frozen sea'
EUROPEAN SPACE AGENCY NEWS RELEASE
Posted: February 23, 2005

The discovery of what could be a frozen sea close to the Martian equator, protected from disappearing by a thin layer of volcanic ash, was reported this week at the first Mars Express Science Conference in Noordwijk, the Netherlands.


This image, taken by the High Resolution Stereo Camera on Mars Express, shows what appears to be a dust-covered frozen sea near the Martian equator. It shows a flat plain, part of the Elysium Planitia, that is covered with irregular blocky shapes. They look just like the rafts of fragmented sea ice that lie off the coast of Antarctica on Earth. The scene is a few tens of kilometres across. Credits: ESA/DLR/FU Berlin (G. Neukum)
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The water that formed the sea appears to have originated beneath the surface of Mars, and to have come out through a series of fractures known as the Cerberus Fossae, from where it flowed in a catastrophic flood. It collected in a vast area about 800 kilometres long and 900 kilometres wide with a depth of about 45 metres. As the water started to freeze, floating pack ice broke up into rafts. These became later covered in ash and dust from volcanic eruptions in the region.

Ice is unstable at the surface of Mars because of the low atmospheric pressure, and sublimates away (changes straight from ice to vapour without passing through the liquid state) into the atmosphere, but some of the ice rafts appear to have been protected by layers of volcanic dust. While the entire sea froze solid, the unprotected ice between the rafts sublimated to leave 'ice plateaus' surrounded by bare rock.

The sparse cratering of this region shows that it cannot have formed more than about five million years ago, meaning this is a relatively young feature.

The question remains as to whether the frozen body of water is still there, or whether the visible floes are just the remains of the sublimation process. Two observations suggest that the ice is still there: first, the submerged craters are too shallow, indicating most of the ice is still in the craters; and second, the surface is too horizontal if the ice had been lost, there would be a greater height variation.

These findings were presented on 21 February at ESA's Mars Express Science Conference at ESTEC in Noordwijk, the Netherlands, where about 250 scientists from all over the world are discussing the first year of scientific results from Mars Express. The complete scientific paper by Dr J. Murray et al. describing the frozen sea results will be published by the journal Nature in March 2005.