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14 mars 2009 6 14 /03 /mars /2009 09:01

  Une fuite dans le système d'alimentation en hydrogène ayant conduit au report du lancement, la navette devrait décoller cette fois dans la nuit de dimanche à lundi (vers une heure du matin, heure française).

   Si tout se passe bien vous pourrez suivre les opérations sur la chaîne de la NASA.

   Parmi les travaux les plus spectaculaires sont prévus l'ajout, sur l'ISS, de deux panneaux solaires ainsi que l'allongement des pourtrelles permettant de les supporter. Ces extensions sont en jaune sur l'écusson symbole de la mission. On utilisera pour cela le bras de télémanipulation à l'extrême limite de ses possibilités
   Voici en Anglais la description de la mission (source NASA).




STS-119 is the 125th space shuttle flight, the 28th flight to the station, the 36th flight for Discovery and the first flight  in 2009. Eight flights to station and one to NASA’s Hubble Space Telescope remain before the shuttles retire in 2010.



The flight features two of the three former school teachers selected as mission specialists in the 2004 Educator Astronaut Class. Teacher-turned-astronaut Dottie Metcalf-Lindenburger is targeted to launch in February 2010.



The truss is a high-tech girder structure made up of 11 segments. It provides the backbone for the station, supporting  the U.S. solar arrays, radiators and other equipment.



To install the S6 truss segment, the station's robotic arm must extend its reach just about as far as it will go (about 57 feet), leaving it with very little room to maneuver.



The S6 truss segment weighs a little more than 31,000 pounds.



After S6 installation, the truss will be 335 feet long.



Each solar array wing has two 115-foot-long arrays, for a total wing span of 240 feet, including the equipment that connects the two wings and allows them to twist as they track the sun.



Altogether, the station’s arrays can generate as much as 120 kilowatts of usable electricity –enough to provide about forty-two 2,800-square-foot homes with power. The addition of the S6 will nearly double the amount of power for station science —from 15 kilowatts to 30 kilowatts.



The Urine Processing Assembly that removes impurities from urine in an early stage of the recycling process is not working. The entire Water Recovery System was delivered and installed during the STS-126 mission in November. Astronauts were able to coax it into use by performing in-flight maintenance, but a distillation unit failed after Endeavour's

departure. The replacement unit will fly in Discovery's middeck and be installed by Sandra Magnus while other crew members are working on the mission's second spacewalk.



Discovery will fly one heat shield tile underneath its left wing that will have a bump raised 0.25 inches so that heating effects are monitored at about Mach 15 during reentry, when thesmooth, laminar flow of air close to the shuttle’s surface becomes turbulent or is disrupted. This information will support computer modeling and design efforts for the shuttle and NASA’s next-generation spacecraft.

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Published by Didier BARTHES - dans Actualités
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grelots 17/03/2009 22:24

Merci pour l'info