国产热热热精品,亚洲视频久久】日韩,三级婷婷在线久久,99人妻精品视频,精品九热人人肉肉在线,AV东京热一区二区,91po在线视频观看,久久激情宗合,青青草黄色手机视频

WORLD> America
NASA hopeful repairs will permit Discovery's Sunday launch
(Agencies)
Updated: 2009-03-15 14:19

CAPE CANAVERAL– NASA is unsure what caused the hydrogen gas leak that prevented space shuttle Discovery from flying, but nonetheless will attempt another launch Sunday.


In this image provided by NASA space shuttle Discovery sits on launch pad 39A at NASA's Kennedy Space Center in Cape Canaveral Florida. [Agencies] 

Shuttle managers are hopeful that repairs at the launch pad have solved the problem.

There's "a potential risk" that the leak will recur, said Mike Moses, chairman of the mission management team. That would mean yet another delay for the international space station construction mission, which already is running more than a month late.

"We did everything we could, which is to replace all the hardware," Moses told reporters Saturday. "Yeah, we'd like to have that root cause, because now you'd feel comfortable. But I'm still going to sleep just as good tonight knowing that our chances tomorrow are really good that we did lick this problem."

NASA has until Tuesday to launch Discovery before having to wait for a Russian Soyuz rocket that is set to blast off to the space station March 26.

The latest delay occurred Wednesday, just hours before liftoff, as NASA was almost finished loading Discovery's external fuel tank. Hydrogen gas began leaking where a vent line hooks up to the tank.

NASA replaced that hookup and a pair of seals and, in fact, fell a few hours behind in countdown preparations because of an assembly issue. Nothing obvious was wrong with the removed parts. One of the seals was slightly rolled up along the edge, and the hookup itself was discolored in one spot. But neither of those issues may have caused the leak, said launch director Mike Leinbach.

"I just don't have a smoking gun," Leinbach said. He acknowledged it's a little unusual to continue the countdown in such a case, but he stressed it's not a launch safety issue because the launch will be canceled again if there's a leak.

Discovery's previous delays - which have stretched over month - were caused by hydrogen gas valves in the shuttle engine compartment. NASA ordered extra tests and kept replacing the valves to make sure they were safe to fly. One of these valves broke on the last shuttle launch in November.

Waiting to fly since mid-February, Discovery and seven astronauts are set to carry up one last set of solar wings for the space station.

   Previous page 1 2 Next Page  

蚌埠市| 新安县| 鄢陵县| 高唐县| 张家港市| 和林格尔县| 璧山县| 建宁县| 九台市| 澄城县| 花垣县| 盘锦市| 神木县| 高密市| 河间市| 湛江市| 内丘县| 中方县| 香河县| 望城县| 健康| 寿光市| 台北县| 余江县| 景洪市| 依安县| 开平市| 金秀| 长泰县| 定西市| 兴城市| 东兴市| 玛纳斯县| 江陵县| 当雄县| 巴彦淖尔市| 都匀市| 石景山区| 武宁县| 乐山市| 庆阳市|