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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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Farewell to Complex 36
Following the 145th and final Atlas rocket liftoff from Cape Canaveral's Complex 36, officials "toast" the historic two-pad site and its blockhouse. Then the spotlights illuminating the pads are turned off as the complex "goes dark." (10min 50sec file)

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Shuttle crew in training
Astronauts Soichi Noguchi and Steve Robinson go under water in the Neutral Bouyancy Lab's gigantic pool to practice spacewalk activities for the upcoming STS-114 return-to-flight space shuttle mission. (3min 45sec file)
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Visiting the Cape
The STS-114 return-to-flight space shuttle crew visits Kennedy Space Center to inspect Discovery and the new sensor boom that will look for orbiter launch damage. (2min 22sec file)
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Day of Remembrance
NASA pays tribute to those lost while furthering the cause of exploration, including the Apollo 1, Challenger and Columbia crews, during this Day of Remembrance memorial from agency headquarters on Jan. 27. (38min 58sec file)

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Spacewalk highlights
The Expedition 10 conducts a successful spacewalk outside the International Space Station to mount a German robotic arm and Russian science package to the Zvezda service module's exterior. (5min 07sec file)
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Huygens science update
One week after the Huygens probe landed on Saturn's moon Titan, scientists hold a news conference to announce additional results and describe more pictures from the mission. (69min 02sec file)

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First measurement of Titan's winds from Huygens
EUROPEAN SPACE AGENCY NEWS RELEASE
Posted: February 9, 2005

Using a global network of radio telescopes, scientists have measured the speed of the winds faced by Huygens during its descent through the atmosphere of Titan. This measurement could not be done from space because of a configuration problem with one of Cassini's receivers. The winds are weak near the surface and increase slowly with altitude up to about 60 km, becoming much rougher higher up where significant vertical wind shear may be present.


An artist's concept shows Huygens parachuting to Titan after deployment from the Cassini orbiter. Credit: EADS Astrium
 
Preliminary estimates of the wind variations with altitude on Titan have been obtained from measurements of the frequency of radio signals from Huygens, recorded during the probe's descent on January 14. These 'Doppler' measurements, obtained by a global network of radio telescopes, reflect the relative speed between the transmitter on Huygens and the receiver on the Earth. Winds in the atmosphere affected the horizontal speed of the probe's descent and produced a change in the frequency of the signal received on Earth. This phenomenon is similar to the commonly heard change in pitch of a siren on a speeding police car.

Leading the list of large radio antennas involved in the programme were the NRAO Robert C. Byrd Green Bank Telescope (GBT) in West Virginia, USA, and the CSIRO Parkes Radio Telescope in Australia. Special instrumentation designed for detection of weak signals was used to measure the 'carrier' frequency of the Huygens radio signal during this unique opportunity. The initial detection, made with the 'Radio Science Receivers' on loan from NASA's Deep Space Network, provided the first unequivocal proof that Huygens had survived the entry phase and had begun its radio relay transmission to Cassini.

The very successful signal detection on Earth provided a surprising turnabout for the Cassini-Huygens Doppler Wind Experiment (DWE), whose data could not be recorded on the Cassini spacecraft due to a commanding error needed to properly configure the receiver. "Our team has now taken a significant first step to recovering the data needed to fulfil our original scientific goal, an accurate profile of Titan's winds along the descent trajectory of Huygens," said DWE's Principal Investigator Dr Michael Bird (University of Bonn, Germany). The ground-based Doppler measurements were carried out and processed jointly by scientists from the NASA Jet Propulsion Laboratory (JPL, USA) and the Joint Institute for VLBI in Europe (JIVE, The Netherlands) working within the DWE team.

Winds on Titan are found to be flowing in the direction of Titan's rotation (from west to east) at nearly all altitudes. The maximum speed of roughly 120 metres per second (430 km/h) was measured about ten minutes after the start of the descent, at an altitude of about 120 km. The winds are weak near the surface and increase slowly with altitude up to about 60 km. This pattern does not continue at altitudes above 60 km, where large variations in the Doppler measurements are observed. Scientists believe that these variations may arise from significant vertical wind shear. That Huygens had a rough ride in this region was already known from the science and engineering data recorded on board Huygens.

"Major mission events, such as the parachute exchange about 15 minutes into the atmospheric flight and impact on Titan at 13:45 CET, produced Doppler signatures that we can clearly identify in the data," Bird said.

At present, there exists an approximately 20-minute interval with no data between the measurements at GBT and Parkes. This gap in Doppler coverage will eventually be closed by data from other radio telescopes which are presently being analysed. In addition, the entire global set of radio telescopes performed Very Long Baseline Interferometry (VLBI) recordings of the Huygens signal to determine the probe's precise position during the descent.

"This is a stupendous example of the effectiveness of truly global scientific co-operation," said Jean-Pierre Lebreton, ESA Huygens Project Scientist. "By combining the Doppler and VLBI data we will eventually obtain an extremely accurate three-dimensional record of the motion of Huygens during its mission at Titan," he concluded.

The radio astronomy support of the Huygens mission is co-ordinated by JIVE and JPL and involves the Netherlands Foundation for Research in Astronomy (ASTRON, The Netherlands), the University of Bonn (Germany), Helsinki University of Technology (Espoo, Finland), the MERLIN National Facility (Jodrell Bank, UK), the Onsala Space Observatory (Sweden), the NASA Jet Propulsion Laboratory (Pasadena, USA), the National Radio Astronomy Observatory (NRAO, Green Bank, USA, and Socorro, USA), the CSIRO Australia Telescope National Facility (ATNF, Sydney, Australia), the University of Tasmania (Hobart, Australia), the National Astronomical Observatories of China, the Shanghai Astronomical Observatory (Shanghai and Urumqi, China) and the National Institute of Information and Communications Technologies (Kashima Space Research Center, Japan).

The Joint Institute for VLBI in Europe is hosted by ASTRON and funded by the national research councils, national facilities and institutes of The Netherlands (NOW), the United Kingdom (PPARC), Italy (CNR), Sweden (Onsala Space Observatory, National Facility), Spain (IGN) and Germany (MPIfR). The National Radio Astronomy Observatory is operated by Associated Universities, Inc., under a co-operative agreement with the National Science Foundation. The Australia Telescope is funded by the Commonwealth of Australia for operation as a National Facility managed by CSIRO. The Jet Propulsion Laboratory is operated by the California Institute of Technology under contract to NASA.

The Cassini-Huygens mission is a co-operation between NASA, ESA and ASI, the Italian space agency. The Jet Propulsion Laboratory (JPL), a division of the California Institute of Technology in Pasadena, is managing the mission for NASA's Office of Space Science, Washington DC. JPL designed, developed and assembled the Cassini orbiter while ESA operated the Huygens atmospheric probe.  

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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