美国“发现号”航天飞机的宇航员史蒂夫.鲍文和阿尔文.德鲁正在进行两次太空行走中的第二次，也是最后一次。正在执行最后一次使命的“发现号”航天飞机目前停靠在国际空间站。
两位宇航员正在修理一个损坏的泵，并进行存储区域外的其它维护工作。他们星期二完成了6个半小时的太空行走。
“发现号”将于星期日脱离空间站踏上两天的归途。自从“发现号”1984年首次升空后，这是它的第39次，也是最后一次使命。
“发现号”退役后预计将被安放在美国首都华盛顿的史密森国家航空航天博物馆或在首都以外的其它地方展出。
American astronauts Steve Bowen and Alvin Drew are taking the last of two spacewalks of the final mission of the U.S. space shuttle Discovery, which is docked at the International Space Station.
The two men are working on a broken pump and doing other maintenance work on an outside storage area. They completed a six-and-a-half hour spacewalk on Tuesday.
Discovery undocks from the space station Sunday for the two-day journey home. First launched in 1984, this is Discovery's 39th and final mission.
When it is retired,Discovery is expected to be placed on exhibit at the Smithsonian's National Air and Space Museum in Washington, or at its annex location just outside the U.S. capital.
