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
2021-07-23
53
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/lSJ7777K
0
大学英语六级
相关试题推荐
Forthispart,youareallowed30minutestowriteanessayonChineselearning.YouressayshouldincludewhypeopleneglectCh
A、Gamesaretragicallyboring.B、Gamesarefulloffun.C、Gamescanmakepeoplecry.D、Gamesmeansomethingmoretous.D
随着生活水平的提高,人们的营养状况得到改善,“发福者”日渐增多。肥胖(obesity)可不仅仅是影响人们的体型而已。研究发现,肥胖是一个特别重要的与生活方式有关的癌症决定因素。世界卫生组织的国际癌症研究机构(theInternationalAgency
CollegeStudents’Booklist1.这是一所大学里学生所购书籍的变化2.你对于学生选择书籍类别变化的评论3.哪类书籍买得比较多?说明原因
A、Byinformingpeoplethatit’sanincurabledisease.B、Byprovidingeffectivemedicinetostopitstransmission.C、Bydisciplin
A、Findingagoodjobinafamousinternationalcompany.B、Shapingthefutureofyourcountryandthewholeworld.C、Bringinghon
Theincreaseinglobaltrademeansthatinternationalcompaniescannotaffordtomakecostlyadvertisingmistakesiftheywantt
A、Laughingisalearnedbehavior.B、Laughingisagoodmedicinetopatients.C、Laughingiseasierthanbattlingwithanillness.
A、ItwasestablishedinGeorgeWashingtonUniversityin1937.B、ItwasestablishedintheNationalMuseumofAmericanHistoryin
随机试题
育婴职业是以()等级划分的。
维持蛋白质β-片层结构的化学键主要是
不属于“实名制"挂号意义的是
基础设计中,构造上通过限制刚性基础的()来满足刚性角的要求。
在持续经营的情况下,分期核算的会计期间是人为划分的。()
银行对一年未发生收付活动且未欠开户银行债务的单位银行结算账户,应通知单位自发出通知之日起()日内办理销户手续,逾期视同自愿销户,未划转款项列入久悬未取专户管理。
下列说法正确的是()。
排除求助者精神病性精神障碍的依据不包括()。求之助者的性格特点不包括()。
公安部于2011年9月修订印发了新的《公安机关人民警察职业道德规范》,此次印发的《公安机关人民警察职业道德规范》是对1994年版的修订与完善。()
A、Sightdeposits.B、Certificatesofdeposit.C、Timedeposits.D、Savingsdeposits.BCDs(可转让大额存单)应指B项“存款单”。sightdeposit活期存款。time
最新回复
(
0
)