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
The US space agency’s(NASA) Mars rovers are celebrating a remarkable five years on the Red Planet. The fist rover, named Spi
The US space agency’s(NASA) Mars rovers are celebrating a remarkable five years on the Red Planet. The fist rover, named Spi
admin
2011-02-05
33
问题
The US space agency’s(NASA) Mars rovers are celebrating a remarkable five years on the Red Planet.
The fist rover, named Spirit, landed on January 3, 2004, followed by its twin, Oportunity, 21 days later.
It was hoped the robots would work for at least three months, but their longevity in the freezing Martian conditions has surprised everyone.
The rovers’ data has revealed much about the history of water on the equator of Mars billions of years ago.
"These rovers are incredibly resilient considering the extreme environment the hardware experiences every day," said John Callas, project manager for Spirit and Opportunity at NASA’s Jet Propulsion laboratory in Pasadena, California. "We realize that a major component on either vehicle could fail at any time and end a mission with no advance notice, but on the other hand, we could accomplish the equivalent of four more prime missions on each rover in the year ahead. "
Spirit is exploring a 150 km-wide bowl-shaped depression known as Gusev Crater. It has found an abundance of rock and soils bearing evidence of extensive exposure to water.
Opportunity is on the other side of the planet, in a flat region known as Meridiani Planum. Its data have shown conclusively that this part of Mars experienced liquid water on its surface. The sedimentary rocks at its study location were laid down under gently flowing surface water.
The rovers are now showing some serious signs of wear and tear.
Spirit has to driver backwards everywhere it goes because of a jammed wheel, and Opportunity’s robotic arm has a glitch in a shoulder joint because of a broken electrical wire.
There have been times also when the vehicles have been dangerously short on power because of the dust covering on their solar panels.
When Spirit and Opportunity do eventually fail, NASA will have to wait awhile for its next surface mission.
It recently delayed this year’s planned launch of a much more capable vehicle, known as the Mars Science Laboratory (MSL) to 2011. The rover project has been beset by technical and budgetary problems. The decision was taken not long after Europe also postponed its rover venture known as ExoMars. Officials cited cost concerns. It is likely all surface missions in future for NASA and the European Space Agency will be joint affairs because of the high cost if getting spacecraft down on to the planet.
NASA lost contact with its static Phoenix lander in November. It was operating in much more difficult conditions at a high-latitude location.
Why will NASA and the European Space Agency combine their efforts to explore Mars in the future?
选项
答案
Because of the high cost/expense
解析
转载请注明原文地址:https://kaotiyun.com/show/kxVK777K
本试题收录于:
C类竞赛(非英语专业本科)题库大学生英语竞赛(NECCS)分类
0
C类竞赛(非英语专业本科)
大学生英语竞赛(NECCS)
相关试题推荐
(1)RemembertheStoneAgedaysofresearchbackinelementaryschoolandmiddleschool?Wewouldspendcountlesshoursdigesting
BenbecameinterestedinMongoliaearlyinlife.Whenhewas9yearsold,hereadabookaboutMarcoPolo,abouthowMarcoPolo
ChinatownsarecommoninsomeUScities.Inthemid-19thcentury,they【T1】________thewestcoastfromSanDiego,Californiato
DomesticViolenceandAbuseDomesticabuseoccurswhenonepersoninanintimaterelationshipormarriagetriestodominate
SleepWhenyouworryaboutneedingsleepandtwistaround,tryingtofindacomfortableposition,you’reprobablyonlymakin
Itisgenerallynot________forexpectantmotherstotravelbyairafterthe28thweekofpregnancy.
(1)Browsers,piecesofinternetsoftwarethatpeopleprobablyspendmoretimewiththantheydoinbed,havelongbeenboringa
(1)MostadultsintheU.S.whoscreenpositivefordepressionarenotbeingtreatedfordepression,accordingtoresultsfromM
PassageThreeWhatdoes"disappearingundertheradar"probablymeaninPara.2?
ARemarkableBicyclistandaRemarkableHumanBeingJustinJohnsonisaremarkablehumanbeing.Hewasbornwithnumerousha
随机试题
暑淫证致病特点为
A.急性胃肠炎B.上消化道大出血C.肾病综合征D.肝性脑病E.肾小球肾炎不洁食物会诱发
A.肝郁气滞胁痛B.肝郁化火胁痛C.肝郁血虚胁痛D.肝郁阴虚胁痛E.肝胆实火胁痛龙胆泻肝汤主治
M胆碱受体阻断药的临床应用错误的是
欲对某企业的资产负债率(62%)和产品销售率(95%)进行标准化处理,两项指标的算术平均数和标准差分别为:61%、3%和96%、2%。正确的处理结果是( )。
美国游客比尔在井冈山旅游时,不慎丢失护照。作为井冈山的地陪你怎样给比尔提供有效的帮助?()。
根据以下资料,回答111-115题。注:图中数据为基于5级量表的得分,5分表示安全感最高,1分表示安全感非常低。下列关于2007年我国城乡居民各种生活领域安全感得分的说法不正确的是()。
简述学校教育的主要价值。
InlearningEnglishweshouldnot______ourstudentsoftheirmistakesallthetime.
Moralresponsibilityisallverywell,butwhataboutmilitaryorders?Isitnotthesoldier’sdutytogiveinstantobedienceto
最新回复
(
0
)