2. 考研
  3. For a few minutes on the afternoon of Friday April 8th millions of eyes were focused on Cape Canaveral in Florida, and shortly a

For a few minutes on the afternoon of Friday April 8th millions of eyes were focused on Cape Canaveral in Florida, and shortly a

admin2019-08-08  94
问题    For a few minutes on the afternoon of Friday April 8th millions of eyes were focused on Cape Canaveral in Florida, and shortly afterwards on a remote "drone" barge a couple of hundred miles downrange in a choppy Atlantic Ocean.
   【F1】The cause of all this attention was SpaceX’s launch of a heavy payload to space, with a later meeting with the International Space Station, and a critical attempt to return the 1st stage booster rocket safely to Earth.
   As reported by pretty much every media outlet across the planet, the Falcon 9 made a gloriously easy-looking powered return and landing on SpaceX’s drone ship.
   So what’s the big deal?
   【F2】First getting the biggest and costliest piece of launch hardware back in one piece offers the possibility of reusing it and lowering the expense of reaching space. Back in the last year, SpaceX had already got a Falcon 9 booster to return to within shouting distance of where it had launched from some ten minutes earlier—on a neighboring pad at Cape Canaveral.
   【F3】Although it remains to be seen how well these rockets hold up to reconditioning and relaunch, the basic idea is sound Reuse means drastically lower launch costs in the long run. It might cost $60 million to build one of SpaceX’s boosters, but on a few hundred thousand dollars to refuel it. Even if making it flight-worthy again costs several million dollars of engineering tinkering and fixing, that’s still an enormous saving.
   【F4】As Elon Musk and many others have long stated, dropping the cost per-unit-mass of launching to space is critical if our species is going to explore and utilize the solar system. It’s also the key to ensuring our long-term survival.
   Mars has a long lure, and SpaceX is in many ways built from the ground up to create the bridge to our 4th planet. 【F5】But apart from simply getting off the Earth and hauling infrastructure and people to this red world, you also have to deposit all of that safely on the surface. Mars is tricky in this respect It may be a less massive world, with a gentler gravity field, but it also has a pitifully thin atmosphere that makes landing stuff a huge challenge because there’s little to "grab onto" as you come rushing down from orbit.
   Small scientific robots and rovers are already pushing the limits of what we can get to the Martian surface in one piece. What’s really needed is the ability to bring a whole launch vehicle down, with tons and tons of payload.
【F5】
选项
答案但是，除了飞离地球、把基础设施和人们运送到这个红色世界，你还必须将这所有的人和物安全降落在火星表面。
解析 ①本句是语法上的简单句，句子主干是主谓宾结构。句首的But表明本句与上句存在转折关系。②介词短语apart from后接两个并列的动名词短语，分别是getting off the Earth和hauling infrastructure and people to…，后者指运送大批人和基础设施。③this red world根据上下文可知指火星；deposit all of that中的all of that指前句提到的人和基础设施。
转载请注明原文地址:https://kaotiyun.com/show/rG2Z777K
0

考研英语一

相关试题推荐
随机试题
最新回复(0)