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
68
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、Hecompletelychangedthecompany’sculture.B、Hecollectedpaintingsbyworld-famousartists.C、Hetookoverthesalesdepar
A、Notenoughmaintenance.B、Peopledidn’tcare.C、Alackofregulationovervisitors.D、Badconstruction.C
A、It’satraditionalEuropeanfestival.B、ItfallsonthedaybeforeEaster.C、Thetraditionalcelebrationisdecoratingeggs.D
A、Afitnessprogramofferedtothegeneralpublic.B、Aphysicalexercisetobuildupmuscles.C、Aprogramthatmakespeoplekeep
A、Thespeakerusesmoregreenthanbrown.B、Thespeakerusesshadowsaroundthetrees.C、Thespeakerusesthegoldenbackground.
Let’sallstopjudgingpeoplewhotalktothemselves.Newresearchsaysthatthosewhocan’tseemtokeeptheirinnermonologues
A、Theybecamemorepopular.B、Theyweremoreregulated.C、Theybecamebetterproduced.D、Theybecamelesshonest.B录音提到,两个法令的出台为
A、Walkingaroundtheaudience.B、Smilingwhileexplainingthenotions.C、Tellingsomejokesduringthespeech.D、Sharingsomepe
Tsunamis[A]UpuntilDecemberof2004,thephenomenonoftsunamiwasnotonthemindsofmostoftheworld’spopulation.Tha
Tsunamis[A]UpuntilDecemberof2004,thephenomenonoftsunamiwasnotonthemindsofmostoftheworld’spopulation.Tha
随机试题
关系数据库分为基于PC的数据库和大型数据库两种类型,下列属于基于PC的数据库的是()
FX2N系列可编程序控制器在使用计数器指令时需要配合使用()指令。
膝关节的支持韧带不包括
根据企业破产法律制度的规定,下列主体中,可以担任管理人的是()。
2016年7月31日,甲公司应付乙公司的款项420万元到期,因经营陷于困境,预计短期内无法偿还。当日,甲公司就该债务与乙公司达成的下列偿债协议中,属于债务重组的有()。
2×21年1月1日,甲公司就某写字楼的第18层与乙公司签订了一份租赁协议。有关资料如下:(1)不可撤销租赁期为5年,不含税租金为每年10万元;在第5年年末,甲公司有权选择以每年10万元续租5年,也有权选择以200万元购买该楼层。每年租金应于每年年
()四方面构成了美术教学的完整过程。
对教育规律与教育方针两者关系的说法,错误的有()
设A从原点出发,以固定速度v0沿y轴正向行驶,B从(x0,0)出发(x0<0),以始终指向点A的固定速度v1朝A追去,求B的轨迹方程.
A、Whenotherareasofyourlifebeginstobeaffected.B、Whenyoubegintofeellonelyandempty.C、Whenyoubegintodateonlin
最新回复
(
0
)