首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
A、They are the smallest satellites. B、They are made by college students. C、They are powered by water. D、They are backed by NASA.
A、They are the smallest satellites. B、They are made by college students. C、They are powered by water. D、They are backed by NASA.
admin
2020-11-04
40
问题
A group of college students is hoping to place a satellite powered only by water into an orbit around the moon. The students are from Cornell University in the state of New York. They are taking part in a competition called the Cube Quest Challenge. It is a program of NASA, the American space agency. The Cornell team is called the CisLunar Explorers. The word "cislunar" means "between Earth and the moon. " The challenge is simple: to design, build and deliver "flight-qualified, small satellites. " NASA officials say the satellites must be able to perform "advanced operations near and beyond the moon. " Ten teams are taking part in the competition. But the CisLunar Explorer satellites are different. They are the only ones using water to power their spacecraft. The idea for a water-powered vehicle came from Mason Peck, who works at Cornell University. He once worked as NASA’s chief technologist. He has always wanted to use something other than rockets to push spacecraft beyond Earth. " A lot of the mass we send into orbit these days is in the form of rockets—the only way we get anything into space," he said, in a Cornell press release. " But what if we could use what’s already there? If we could do that, if we could refuel spacecraft while they’re already in space..."
The spacecraft is shaped like the English letter L. It measures about 30 centimeters in length, and the two pieces are connected. Water is stored in the lower part of the satellite. The sun will separate the water into two elements: hydrogen and oxygen. When one combines hydrogen and oxygen with a spark, an explosion results. This provides a forward movement, known as thrust. The CisLunar Explorer team has an unusual way to guide its spacecraft. The idea is to copy how old-time sailors used the moon, sun and stars to fix their position on the oceans. The satellite is equipped with cameras. The cameras will take pictures of the sun, Earth and the moon and compare their positions and their size. Based on where the sun, moon and Earth are at any given time, the CisLunar Explorers will do the mathematics to find their position. The competition is being held in four parts. The Cornell team has been among the top three competitors during parts one and two. The final three winners will get to ride on NASA’s space launch system in early 2018.
Questions 16 to 18 are based on the recording you have just heard.
16. What makes the CisLunar Explorer satellites different?
17. Where did the CisLunar Explorer team get the idea?
18. How does the CisLunar Explorer team guide its spacecraft?
选项
A、They are the smallest satellites.
B、They are made by college students.
C、They are powered by water.
D、They are backed by NASA.
答案
C
解析
转载请注明原文地址:https://kaotiyun.com/show/y3P7777K
0
大学英语六级
相关试题推荐
A、Cognitivestimulation.B、Communityactivity.C、Balanceddiet.D、Freshair.A讲座中提到,以前的一些研究表明,通过一些精神刺激活动来挑战大脑可能会有助于减少认知衰退,Burke表
A、Biasedsourcesofinformation.B、Ignoranceofculturaldifferences.C、MisinterpretationofShakespeare.D、Tendencytojumpto
A、Theybestboostproductsaleswhenputonline.B、TheyaremosteffectivewhenappearingonTV.C、Theyarebecomingmoreandmo
A、Healthconditionsimprovewithtimespentwatchinghealthyprograms.B、Comedyvideoscancuremostpeopleofchronicheartatt
A、Tofindagoodjob.B、Topassexams.C、Toavoidpressurefromsociety.D、Tobecomemoreclever.A
A、Theanimaleatthingsthataresprayedwithpesticides.B、Theanimaleatthingsthathavebeengeneticallymodified.C、Theani
Cansocietiesberichandgreen?[A]"Ifoureconomiesaretoflourish,ifglobalpovertyistobeeliminatedandifthewell-bei
A、Thegovernmentwantstoshowmoreconcernforitspeople.B、Thegovernmentneedstoimportmoregoodsfromabroad.C、TheJapan
A、Themail.B、Theposter.C、Thetext.D、Themagazine.A四个选项都是不同形式的媒体,推测本题与某种媒体的特点有关。听音时应注意各个媒体的具体信息。讲座提到,最广泛使用的广告媒体是直接媒体,而信件是最普遍
随机试题
从所给的四个选项中,选择最合适的一个填入问号处,使之呈现一定的规律。()
[2011专业案例真题下午卷]110kV架空送电线路架设双地线,采用具有代表性的酒杯塔,塔的全高为33m,双地线对边相导线的保护角为10°,导地线高度差为3.5m,地线平均高度为20m,导线平均高度为15m,导线为LGJ—500/35(直径d=30mm)钢
使用估算模式时,需要提供的点源数据包括()
依据《行政处罚法》的规定,下列关于行政处罚执行程序的说法,正确的是()。
公路工程施工中,项目经理部应文明施工,在项目部或工程适当位置应设置公示标志,内容包括()。
下列各项中,关于未领取“一照一码”营业执照的企业申请变更税务登记的说法,不正确的是()。
风险管理最根本的动力来源是()
在“光合作用吸收二氧化碳释放氧气”一节中,某教师安排了实验:“二氧化碳是光合作用必需的原料吗?”实验过程如下:(一)提出问题二氧化碳是光合作用必需的原料吗?(二)作出假设二氧化碳是光合作用必需的原料,即没有二氧化碳植物就不能进行光合作用。(三)制
某宾馆有6个空房间,3间在一楼,3间在二楼。现有4名客人要入住,每人都住单间,都优先选择一楼房间。问宾馆共有多少种安排?
在一个采用(16)数据库体系结构的网络数据库应用系统中,计算机C上运行着 DBMS软件和应用程序,并存有所有的用户数据,其余各节点作为终端通过通信线路向计算机C发出数据库应用请求。
最新回复
(
0
)