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
So Many "Earths" The Milky Way(银河)contains billions of Earth-sized planets that could support life. That’ s the finding of a
So Many "Earths" The Milky Way(银河)contains billions of Earth-sized planets that could support life. That’ s the finding of a
admin
2014-08-13
84
问题
So Many "Earths"
The Milky Way(银河)contains billions of Earth-sized planets that could support life. That’ s the finding of a new study. It draws on data that came from NASA’ s top planet-hunting telescope.
A mechanical failure recently put that Kepler space telescope out of service. Kepler had played a big role in creating a census of planets orbiting some 170, 000 stars. Its data have been helping astronomers predict how common planets are in our galaxy. The telescope focused on hunting planets that might have conditions similar to those on Earth.
The authors of a study, published in The Proceedings of the National Academy of Sciences, conclude that between 14 and 30 out of every 100 stars, with a mass and temperature similar to the Sun, may host a planet that could support life as we know it. Such a planet would have a diameter at least as large as Earth’ s, but no more than twice that big. The planet also would have to orbit in a star’ s habitable zone. That’ s where the surface temperature would allow any water to exist as a liquid.
The new estimate of how many planets might fit these conditions comes from studying more than 42, 000 stars and identifying suitable worlds orbiting them. The scientists used those numbers to extrapolate(推算)to the rest of the stars that the telescope could not see.
The estimate is rough, the authors admit. If applied to the solar system, it would define as habitable a zone starting as close to the Sun as Venus and running to as far away as Mars. Neither planet is Earthlike(although either might have been in the distant past). Using tighter limits, the researchers estimate that between 4 and 8 out of every 100 sunlike stars could host an Earth-sized world. These are ones that would take 200 to 400 days to complete a yearly orbit.
Four out of every 100 sunlike stars doesn’ t sound like a big number. It would mean, however, that the Milky Way could host more than a billion Earth-sized planets with a chance for life.
The new finding is based on a thorough study of 170, 000 stars in the Milky Way.
选项
A、Right
B、Wrong
C、Not mentioned
答案
B
解析
第四段第一句表明,这项新评估源于对超过4.2万颗星球的分析,而非源于对17万颗星球的分析。
转载请注明原文地址:https://kaotiyun.com/show/zHQd777K
本试题收录于:
职称英语理工类C级题库职称英语分类
0
职称英语理工类C级
职称英语
相关试题推荐
Thegamerequiresustofindouttwosimplebuteffectivewaystosolvethisproblem.
ManyAmericanwomenhaveapoorknowledgeofcancer.MostAmericanwomenknowtoolittleabouthowtolowertheircancerrisk.
ThepassageindicatesthatancienttreatmentsforinjuryanddiseasewereWhatdothemajorityofthepeopleintheworldusef
Lookingtohelptheenvironment?Considerthefollowingsimpleideas.Turnoffelectricaldeviceswhenthey’renotbeinguse
LightNight,DarkStarsThousandsofpeoplearoundtheglobestepoutsidetogazeattheirnightsky.Onaclearnight,with
NewFoodsandtheNewWorldInthelast500years,nothingaboutpeople—nottheirclothes,ideas,orlanguages—haschangeda
NewFoodsandtheNewWorldInthelast500years,nothingaboutpeople—nottheirclothes,ideas,orlanguages—haschangeda
SaunaCeremonial(仪式性的)bathinghasexistedforthousandsofyearsandhasmanyforms,oneofwhichisthesauna.TheFinnsha
AAttractionsofTravellingBLanguageProblemWhenEatingOutCRevolutionCausedbyJetsDHowTravellers’ConcernsAreMe
PoolWatchSwimmerscandrowninbusyswimmingpoolswhenlifeguardsfailtonoticethattheyareintrouble.TheRoyalSoci
随机试题
求在[0,1]上的最大值和最小值.
某钟表店推出一款新手表,标签上标明:天然钻石手表。甲购得后,送有关部门鉴定,结论是人造钻石手表。依据我国《合同法》,甲可以()
增加小麦出粉率,主要影响哪种营养素的营养价值
吐温类表面活性剂溶血作用强弱的顺序是
以下何者不是“典雅主义”的代表人物?
用波长为5.0×10-7m的单色光垂直照射双缝,若知两缝之间的距离为0.5×10-3m,双缝与屏之间的距离为1.2m,则测得此双缝干涉实验中屏幕上方第五级明条纹离中央明条纹中心点的距离为()。
某设备安装工程,由于设备制造原因试车达不到合同约定的验收要求,则()。
【背景资料】某高架桥工程,其中有三跨为普通钢筋混凝土连续梁,需现场浇筑,跨径组合为30m+40m+30m,桥宽18m,桥下净高9m。模板支架在已经上一级批准的施工组织设计中有详细的专项设计。项目经理为节约成本,就地取材,使用了附近工程
安定的住房,是尊严的前提,幸福的第一步。城市如果要让生活更美化,就要从让每个人都住有所居开始。但住房问题又是城市最大的挑战,“房荒是城市特有的问题”。恩格斯1872年的名著《论住宅问题》就提出住房问题的根源是城市和城乡发展不平衡的问题。城市化和工业化带来人
Everyyeartelevisionstationsreceivehundredsofcomplaintsabouttheloudnessofadvertisements.However,federalrulesforbi
最新回复
(
0
)