新托福阅读材料：CoolingsystemfaulthitsInternationalSpaceStation

会计考友

　人类对于宇宙探索的脚步从未停止过，太空中辛勤工作着的众多卫星和宇宙空间站就是最好例证。当然，这些卫星和空间站也会有“生病”的时候。  
　　The crew of the International Space Station have been forced to reduce power after half the cooling system suddenly shut down over the weekend.
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　　Nasa officials insisted the three Americans and three Russians aboard were not in danger.

3 q) i) o2 q+ ^9 d$ V　　Urgent spacewalk repairs are being discussed for this week.

8 x( O0 k8 R- _) R1 _' z, H# F  Q& Z. o　　Without thermal controls, temperatures on the ISS's Sun-facing side can soar to 121C (250F), plunging to minus 157C (-250F) on the dark side, Nasa says.

, e/ U* [% m* x  N- d- M2 j$ a　　"There might be a comfortable spot somewhere in the middle of the station, but searching for it wouldn't be much fun," a statement on its website adds.

% D7 x9 m, {+ Y2 O　　The station is now operating on a single string, the Associated Press reports, and has no safeguard in case of further cooling system failures.

# n' E3 f( v# X; X- B　　Alarms sound
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: H: T, E; x/ b& v& s, H　　Trouble arose on Saturday night when one of the two ammonia-fed cooling loops shut down, triggering alarms throughout the ISS

( i* o5 g; D; G5 y2 r4 T　　The two ammonia lines ensure that all the station's electronic equipment does not overheat.
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  n7 T  @% {1 @* J　　Astronaut Tracy Caldwell Dyson set in motion equipment shutdown procedures and, with crewmate Douglas Wheelock, installed a jumper cable to keep all the rooms cool.

- q4 {8 ?, |& `$ Y: X  |( p　　The Global Positioning System circuit, several power converters and a set of devices that route commands to various pieces of equipment were switched off.

+ Z1 }5 v( z% s4 a1 y　　Two of the four gyroscopes - part of the space station's pointing and navigating system - were initially shut down but the crew installed a jumper cable to bring up a third gyroscope, leaving the station in a much more stable position, AP says.
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　　Flight controllers tried to restart the disabled ammonia pump early on Sunday but the circuit breaker tripped again.
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- D, [1 b: h" e　　Any repairs later this week almost certainly will involve replacing the faulty ammonia pump, a difficult job that would require two spacewalks, AP adds.

1 g9 v" i5 i0 s4 Q　　"It's pretty clear that we're going to want to have a course of action to take as quickly as possible," Nasa spokesman Rob Navias said at the Johnson Space Center in Houston, Texas.
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8 I/ s3 q% g/ `7 R# J: W　　"This is not something we want to linger over."
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. u: [0 G! R, H! c4 M　　Two spare pumps are stored on the outside of the station. Two of the Americans on board are already scheduled to conduct a spacewalk on Thursday for routine maintenance.
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! I5 m8 Q' e# R1 F) r　　No space shuttle visits to the ISS are planned before November.