时间:2018-12-16 作者:英语课 分类:VOA标准英语2009年(十月)


英语课

By Jessica Berman
Washington
29 October 2009


 
Ultraviolet, X-Ray images of gamma-ray burst 
Astronomers 1 have discovered evidence of the oldest and most distant cosmic event ever detected, a burst from a dying star that occurred 13 billion years ago, very soon after the birth of the universe. Scientists hope the discovery of the ancient explosion will bring new insights into the evolution of the cosmos 2.


Astronomers say the high-energy gamma-ray burst from the dying star occurred 630 million years after the so-called Big Bang that is believed to have created the universe nearly 14 billion years ago.


The discovery suggests the so-called Dark Age of the universe, the period after the Big Bang before first-generation stars could fill the cosmos with light, ended much earlier than previously 3 thought. Prior to the discovery, the earliest stellar explosion on record occurred 200 million years later and involved a star much closer to Earth.


Nial Tanvir of the University of Leicester in England headed one of two teams of scientists that discovered the gamma ray blast marking the death of the star.


Tanvir says the explosion of the dying star, or supernova, takes astronomers farther back in time than they have ever been. "... which really is the sort of era, the one last era, that is left undiscovered in cosmology. We have sort of mapped out the Universe to very great distances. And we are now sort of probing into the last era that we really have no observational clue as to what it was really like then," he said.


Tanvir says the discovery gives scientists a place in the sky to direct the earth-orbiting Hubble Space Telescope to look for other clues about the ancient Universe. "We think that if we look deeply enough, we will see a little galaxy 4 there, a galaxy that hosted the star which exploded. Now we know exactly where to look. If we can go, for instance, as we are planning to do with the Hubble Space Telescope, and have a long hard stare at that patch of sky, then we may reveal that galaxy, and therefore learn something about the very early galaxies 5," he said.


Dan Frail 6 at the National Radio Astronomy Observatory 7 in New Mexico is part of a team analyzing 8 the waves of light given off by the star following its explosion, light that has taken more than 13 billion years to reach the Earth. Their observations may reveal what chemicals and compounds were dispersed 9 during the Big Bang.


Until now, Frail says astronomers have presumed these ancient supernovae were brighter, hotter and more massive than the explosion of later generation stars. "And the next explosions that we study at these distances will tell us more about how the first generations of stars and first galaxies were formed. How the metals that make up the stars today got formed, how the light of the Universe got distributed. So, we have a lot to learn from studying these things; studying more examples of these objects," he said.


Two articles describing the discovery of the most distant cosmic object are published this week in the journal Nature.



1 astronomers
n.天文学者,天文学家( astronomer的名词复数 )
  • Astronomers can accurately foretell the date,time,and length of future eclipses. 天文学家能精确地预告未来日食月食的日期、时刻和时长。 来自《简明英汉词典》
  • Astronomers used to ask why only Saturn has rings. 天文学家们过去一直感到奇怪,为什么只有土星有光环。 来自《简明英汉词典》
2 cosmos
n.宇宙;秩序,和谐
  • Our world is but a small part of the cosmos.我们的世界仅仅是宇宙的一小部分而已。
  • Is there any other intelligent life elsewhere in the cosmos?在宇宙的其他星球上还存在别的有智慧的生物吗?
3 previously
adv.以前,先前(地)
  • The bicycle tyre blew out at a previously damaged point.自行车胎在以前损坏过的地方又爆开了。
  • Let me digress for a moment and explain what had happened previously.让我岔开一会儿,解释原先发生了什么。
4 galaxy
n.星系;银河系;一群(杰出或著名的人物)
  • The earth is one of the planets in the Galaxy.地球是银河系中的星球之一。
  • The company has a galaxy of talent.该公司拥有一批优秀的人才。
5 galaxies
星系( galaxy的名词复数 ); 银河系; 一群(杰出或著名的人物)
  • Quasars are the highly energetic cores of distant galaxies. 类星体是遥远星系的极为活跃的核心体。
  • We still don't know how many galaxies there are in the universe. 我们还不知道宇宙中有多少个星系。
6 frail
adj.身体虚弱的;易损坏的
  • Mrs. Warner is already 96 and too frail to live by herself.华纳太太已经九十六岁了,身体虚弱,不便独居。
  • She lay in bed looking particularly frail.她躺在床上,看上去特别虚弱。
7 observatory
n.天文台,气象台,瞭望台,观测台
  • Guy's house was close to the observatory.盖伊的房子离天文台很近。
  • Officials from Greenwich Observatory have the clock checked twice a day.格林威治天文台的职员们每天对大钟检查两次。
8 analyzing
v.分析;分析( analyze的现在分词 );分解;解释;对…进行心理分析n.分析
  • Analyzing the date of some socialist countries presents even greater problem s. 分析某些社会主义国家的统计数据,暴露出的问题甚至更大。 来自辞典例句
  • He undoubtedly was not far off the mark in analyzing its predictions. 当然,他对其预测所作的分析倒也八九不离十。 来自辞典例句
9 dispersed
adj. 被驱散的, 被分散的, 散布的
  • The clouds dispersed themselves. 云散了。
  • After school the children dispersed to their homes. 放学后,孩子们四散回家了。
学英语单词
alberges
apparent superluminal motion
At Ta'mīm, Liwā'
avicine
be noted as
Bermeio, I.
bows down to
broken wave
chances are (that...)
compact technique
conjugate deviation
cradle snatchers
criniere
deep-sea coral
deep-suction share
dependency (group)
Diafurone
discrepance
dog house
dustfree
economically sound
educational channel
epinodosin
esthwaite
fixed point decimal
fleet servicing
Gabriel Daniel
gametrainer
hatefucked
hexakisphosphates
Hinatuan Pass.
hollow jet needle valve
howsoever
Ichenheim
Imhoff tank
immunity resistant
intelligent information management
jacksonite
Kuwaiti monetary unit
lauristons
leather bag
legal delay time
LOBAL
low-intensity radiation
mast-head light
medusas
memaws
mixed phenolalkyd resin
moeketsis
moghania strobilifera (l.) j. st.hil. ex jacks.
moment of sequence
money of exchange
mp-tvs
natural organic substance
niemi
nitroalkenes
normative ethics
nucleogenisis
ovarian follicular Fluid
parenchymatous syphilis
patch of grey
pay good money for
phase change switch
positional response of carbon microphone
Pouzolzia sanguinea
pygahrix roxellance
rank of tensor
reivers
renesting
rtcip
saint-germain-en-laye
samdwich
scrawnier
sea-unicorn
shadow photometer
shafting
shean
simulators
simultaneous flooding
slight negligence
sonar navigation
source transformation
spacing chart
spineless dogfish
sport suit
ST_technology_telephone-equipment
stegana (steganina) nigrithorax
Steinbach am Wald
straight link
stratified medium
strike a raw nerve
toad spittle
tyndallization
utuado
victualing house
visual demonstration
waterproofing mortar
weak roof
Weisskirchen
Welding Monitor
yabba-dabba-doo
Zolicef