US Shuttle Flights Could Resume This Fall
时间:2019-01-03 作者:英语课 分类:VOA2003(上)-科技先知
The U.S. space agency NASA is getting ready to resume shuttle flights as early as September or October. But the return to flight depends on whether the cause of the shuttle Columbia's 1)demise can be found and fixed 2.
NASA is planning to assemble a team to get U.S. space shuttles ready to return to flight by the final quarter of this year.
That plan was revealed in an internal 2)memorandum written Wednesday by the agency's top space flight official, former astronaut William Readdy. NASA made the document public Friday.
In it, Mr. Readdy says a team will prepare to return shuttles to flight as soon as practicable. He makes clear, however, that the schedule depends on findings of an independent board of experts investigating the cause of Columbia's break-up last month. But he sets the goal for the next shuttle mission as early as this coming fall in the United States, beginning in September.
NASA spokesman Joseph Gordon points out that the schedule only suggests the earliest time a shuttle might fly again. "It's just that in this business you have to have a goal," he said. "For practical purposes at this time, no earlier than the fall date or timeframe seems practical. Most likely, it'll be probably later than that - hopefully not much later. But, again, it's all dependent upon the results of the board and on us reacting to those results."
Should a shuttle return to flight late this year, the break would be far shorter than the 32 month moratorium 3 after the 1986 explosion of the Challenger vehicle. But the need to get shuttles back to orbit is more urgent now because they are essential to support the International Space Station.
The next shuttle mission was supposed to be later this month, a mission to exchange station crews.
But as a result of the Columbia disaster, the crew swap 4 will take place in late April or early May, using Russian Soyuz rockets. The three-man U.S. and Russian team now in orbit will return to Earth aboard the Soyuz attached to the station as an emergency escape vehicle. Before their departure, another Soyuz will carry up a two-person replacement 5 crew.
Station commander Ken 6 Bowersox says that, despite the Columbia tragedy, he is not nervous about re-entering the atmosphere. "Entry in any vehicle is always a big deal," he explained. "You are taking a lot of kinetic 7 energy and removing it from a system. That all gets turned into heat. It's a time that's fraught 8 with danger and you need to be careful about everything that goes on during that period. But I wouldn't say that I feel any more apprehension 9 now than many other entries that I've been through."
Although Commander Bowersox and his two colleagues had not expected to return on a Soyuz, they trained on one in Russia as part of routine preparations for an emergency escape from the outpost. They will enter the Soyuz over the weekend to practice the departure procedures.
David McAlary VOA news, Washington.
1)demise [di5maiz]n.死亡,消灭,停止活动
2)memorandum[7memE5rAndEm]n. 备忘录, 便笺, 便函
- It was not the custom for elderly people to mar the picnics with their presence.大人们照例不参加这样的野餐以免扫兴。
- Such a marriage might mar your career.这样的婚姻说不定会毁了你的一生。
- Have you two fixed on a date for the wedding yet?你们俩选定婚期了吗?
- Once the aim is fixed,we should not change it arbitrarily.目标一旦确定,我们就不应该随意改变。
- The government has called for a moratorium on weapons testing.政府已要求暂停武器试验。
- We recommended a moratorium on two particular kinds of experiments.我们建议暂禁两种特殊的实验。
- I will swap you my bicycle for your radio.我想拿我的自行车换你的收音机。
- This comic was a swap that I got from Nick.这本漫画书是我从尼克那里换来的。
- We are hard put to find a replacement for our assistant.我们很难找到一个人来代替我们的助手。
- They put all the students through the replacement examination.他们让所有的学生参加分班考试。
- Such things are beyond my ken.我可不懂这些事。
- Abstract words are beyond the ken of children.抽象的言辞超出小孩所理解的范围.
- There exist many sources of energy both potential and kinetic.存在着许多势能和动能的能源。
- The kinetic theory of gases is the best known example.气体动力学理论就是最有名的例子。
- The coming months will be fraught with fateful decisions.未来数月将充满重大的决定。
- There's no need to look so fraught!用不着那么愁眉苦脸的!
- There were still areas of doubt and her apprehension grew.有些地方仍然存疑,于是她越来越担心。
- She is a girl of weak apprehension.她是一个理解力很差的女孩。