热点话题八:纪念美国登月40周年 | |||
|
|||
重要词组: 补充阅读资料(节选自economist)
Five years ago George Bush outlined a plan to return Americans to the moon in 2020, with an option on going to Mars later. Now that plan is the subject of a rather un-American bout of introspection and self-examination. At the behest of Barack Obama’s newly empowered Office of Science and Technology Policy (OSTP), NASA, America’s space agency, is submitting to an independent review of its human-spaceflight plans in order to determine their future.
The starting point for the review is a simple one: money. Mr Obama’s administration, like every other new government, wishes to impose its own spending plans, and human spaceflight has never been high on its list of priorities. The existing plan for human spaceflight sets NASA on a path that will lead it to consume what one insider estimates to be around $100 billion before the programme is complete. It seems entirely prudent, therefore, for the administration to examine whether this is money well spent.
NASA faces substantial challenges. For example, as currently designed, its plans for a system of rockets to replace the shuttle (known collectively as Ares, the Greek name for Mars) do not fit within the funds that are available, and have been criticised for showing too little innovation and even less progress. NASA’s role, some argue, should be the whizzier business of novel plasma-drives and nanotech-based heat shielding—not “Apollo on steroids” as some people have derisively described Ares. Nor is there any sense of how the proposed moon base that would eventually be built, supposedly as a stepping stone to Mars, can be supported financially.
The difficulty, as ever, is to make the agency properly serve the public that pays for it. Few are suggesting that NASA be eliminated, but such questions reflect the struggle for purpose that it has had since the end of Apollo. Its mission is not human exploration for its own sake, nor off-planet colonisation, yet human spaceflight consumes a large chunk of the budget.
At the moment a shift in priorities that would lead to a direct Mars mission seems unlikely. Even if astronauts return to the moon, though, the means of getting them there must still be decided. One alternative to Ares, proposed by the United Launch Alliance, a joint venture of Lockheed Martin and Boeing, is to use modified versions of their existing Delta 4 and Atlas 5 rockets both to go to the moon and to resupply the space station, but at lower cost. And if Ares is cancelled another winner may be SpaceX, a small Californian firm that is building a series of rockets called Falcon. These will be able to fly cargo to the International Space Station—and, if all goes well in the future, people.
|
|||
|
|||
|
![]() |
评论·留言 |
新闻·热点 | 更多 |
开放课堂 | 更多 |
热荐课程 | 更多 |
哈佛少儿中外教特色2A班-WY-ZP-1... 开班时间:2016-11-15 上课时间:16:30-19:00 价格:8800 在线预约立减50元 新概念II下半册进阶班(49-96课... 开班时间:2017-01-08 上课时间:09:00-11:30 价格:6000 在线预约立减50元 新概念II下半册进阶班(49-96课... 开班时间:2017-01-08 上课时间:18:00-20:30 价格:6000 在线预约立减50元 小升初考证3E笔试3级班-YY-ZS-1... 开班时间:2016-07-04 上课时间:09:00-11:30 价格:3980 在线预约立减50元 新概念II下半册进阶班(49-96课... 开班时间:2016-11-06 上课时间:15:30-18:00 价格:6000 在线预约立减50元