托福阅读：国际空间站冷却系统故障

托福阅读会涉及到各种性质的段子，其中学术类的段子比较多一些，考生在进行托福阅读练习时，也应该选一些类似的段子来模拟练习。下面，小编为大家提供托福阅读材料“国际空间站冷却系统故障”供大家阅读，希望对大家有所帮助。

The crew of the International Space Station have been forced to reduce power after half the cooling system suddenly shut down over the weekend.

Nasa officials insisted the three Americans and three Russians aboard were not in danger.

Urgent spacewalk repairs are being discussed for this week.

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.

“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.

The station is now operating on a single string， the Associated Press reports， and has no safeguard in case of further cooling system failures.

Alarms sound

Trouble arose on Saturday night when one of the two ammonia-fed cooling loops shut down， triggering alarms throughout the ISS

The two ammonia lines ensure that all the station‘s electronic equipment does not overheat.

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.

The Global Positioning System circuit， several power converters and a set of devices that route commands to various pieces of equipment were switched off.

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.

Flight controllers tried to restart the disabled ammonia pump early on Sunday but the circuit breaker tripped again.

Any repairs later this week almost certainly will involve replacing the faulty ammonia pump， a difficult job that would require two spacewalks， AP adds.

“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.

“This is not something we want to linger over.”

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.

No space shuttle visits to the ISS are planned before November.

以上就是托福阅读材料《国际空间站冷却系统故障》，同学们可以积累其中的词汇及优美句式，找到托福阅读段的主题句，了解托福阅读的几个出题点。托福阅读训练是个长期的过程。大家如果每天做几篇阅读，坚持下来，一定会有不小的进步。