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Space station airlock allows equal access

发布时间:2019-03-06 13:02:01来源:未知点击:

By Nicola Jones The International Space Station is scheduled to get its own airlock on Thursday, which will finally give both Russian and American astronauts a door to outer space. Until now, ISS residents who wanted to step outside the station had to wait for a visit from the space shuttle so they could use its airlock. But even then they could only use American spacesuits – the communications system and connections for oxygen and coolant in the shuttle do not work with Russian suits. The new airlock will be able to handle both styles of space wear, refilling them after each use with the different gas pressures required by each. The airlock will be delivered to the station by the Atlantis shuttle and will be installed with the help of robotic arms on the shuttle and ISS. It will be the first time the station’s robotic arm, called Canadarm2, has done any construction work since being installed in April. Computer problems with the arm have caused NASA concern and have played a part in delaying the current mission by almost three months. “I would say we’re fairly confident, but I wouldn’t couch it as a routine operation. There’s a lot of things that have to go right,” says Richard Rodriguez, who works with the ISS program for NASA in Huntsville, Alabama. Bad weather at the launch site could cause further delays. The forecast on Tuesday is for thunderstorms in Florida, which could prevent safe refuelling of the shuttle. The airlock module was designed and built by Boeing at the Marshall Space Flight Center in Huntsville, Alabama. It is six metres long, weighs five tonnes and has two chambers. The first serves as a changing room and closet. It is capable of reducing the air pressure to 70 per cent of that inside the ISS. Astronauts will spend at least an hour in this cramped space, adjusting to the pressure and breathing pure oxygen. That helps to prevent the “bends”, a condition caused by a rapid decrease in pressure. The tiny second room further reduces the pressure to 34 per cent of normal pressure. The airlock will first be used for a mission to attach tanks of oxygen and nitrogen to the outside of the station. These will help replace the small amount of air lost from the station whenever the lock opens, and will serve as an emergency air supply. Boeing suffered an embarrassment last year when two of these air tanks were accidentally thrown out as trash. “They were effectively misplaced,” says Rodriguez. The slip cost Boeing about $750,000,