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These discoveries raised the stakes. Here was a planet similar to our own. Mars might not have cities or civilizations. But it could be home to other smaller life forms like microbes. Chris McKay is N

发表于:2018-12-07 / 阅读(179) / 评论(0) 分类 火星生命

I think it is exciting. Because it would imply that if life arose independently on Mars. The implication is that life is pervasive throughout the universe. This is why Mars has so obsessed scientists.

发表于:2018-12-07 / 阅读(167) / 评论(0) 分类 火星生命

Rice had seen the same thing in Iceland, one of the few places on Earth with similarities to Mars. It too is extremely cold, and most of the water is frozen into glaciers. And also like Mars, buried u

发表于:2018-12-07 / 阅读(183) / 评论(0) 分类 火星生命

For Mars to have rivers, it must once have had streams, rain, clouds and an atmosphere, a planet just like the Earth today-if these were rivers. They had to be sure. The answers would come in 1998 wit

发表于:2018-12-07 / 阅读(191) / 评论(0) 分类 火星生命

William Boynton is professor of planetary sciences at the University of Arizona. And he's dedicated his life to looking for water on Mars. The link between life and water is very strong. Even here in

发表于:2018-12-07 / 阅读(170) / 评论(0) 分类 火星生命

This is one of the reasons why Canada, 这就是为何加拿大 originally a climate change hero -- 它原本是环保英雄- we were one of the first signatories of the Kyoto Accord. 我们是第一批签署京都议定书的国家之一 Now we're

发表于:2018-12-08 / 阅读(147) / 评论(0) 分类 TED演讲娱乐篇

Over centuries, the Irish built a rich heritage of castles and monuments, using an abundance of local stone. Now many of the structures are damaged. The stone is decaying. Thanks in part to Irelands notoriously damp weather, these sites are in danger

发表于:2018-12-26 / 阅读(177) / 评论(0) 分类 自然百科2010年

Of course, any terraforming is still a long way off. The next few expeditions to Mars will definitely be made by machines. NASA, are sending 2 rovers, capable of travelling over 100 meters a day in se

发表于:2019-01-02 / 阅读(160) / 评论(0) 分类 火星生命

Well, hearing that Odyssey had found subsurface water on Mars was enormously exciting for somebody who is involved in planning to send humans to Mars. Water has a number of important uses for us. At t

发表于:2019-01-02 / 阅读(188) / 评论(0) 分类 火星生命

Life on Earth is basically proteins and DNA, so we can wonder if there is life on Mars will also be DNA and proteins, the same type of DNA, the same type of proteins. One might think that DNA is such

发表于:2019-01-02 / 阅读(168) / 评论(0) 分类 火星生命

But there was something even better. Odyssey may not just have found ice. There may also be liquid water, and that means, there could be living creatures there too. Right now, there might be liquid wa

发表于:2019-01-02 / 阅读(196) / 评论(0) 分类 火星生命

But they never got there. The first disappeared into deep space. Another missed its target when its coordinates were confused. One NASA control center was working in metric, the other in feet and inch

发表于:2019-01-02 / 阅读(201) / 评论(0) 分类 火星生命

The ground here is permafrost, a mixture of soil and ice frozen together. A group of Russian scientists have teamed up with NASA to drill down into it in search of microorganisms. It's work that's bee

发表于:2019-01-02 / 阅读(191) / 评论(0) 分类 火星生命

One of these wavelengths corresponds to hydrogen, another wavelength would be iron. Another wavelength would be oxygen. And so you go to the part of the spectrum you are interested in and you see you'

发表于:2019-01-02 / 阅读(183) / 评论(0) 分类 火星生命

Broadcast: Apr 02, 2003 The investigation into what caused the break-up of the U.S. space shuttle Columbia supports the theory that a left wing panel broke off during its mission, possibly playing a r

发表于:2019-01-03 / 阅读(215) / 评论(0) 分类 VOA2003(上)-科技先知

Study: African Aluminum Pots Contain Lead 研究表明非洲铝锅含有铅 Locally made aluminum pots in Cameroon, and probably in much of Africa, are likely to be contaminated with lead ( (Courtesy: Occupational Knowledge International). Locally ma

发表于:2019-01-14 / 阅读(163) / 评论(0) 分类 VOA标准英语2014年(八月)

From Haridwar. I followed the Ganges more than 300 miles South east to the major industry city. India's population has more than doubled in the last forty years. It's now more than 1.2 billion people in the country. The impact on the river has been a

发表于:2019-01-16 / 阅读(135) / 评论(0) 分类 自然百科2015年

And we're replacing that with the largest industrial project in the history of the world, 将它转变成史上最大的工业项目, which is producing the most high-carbon greenhouse gas emitting oil in the world. 生产温室气体排放量最大的

发表于:2019-01-18 / 阅读(161) / 评论(0) 分类 TED演讲商业篇

Over centuries, the Irish built a rich heritage of castles and monuments, using an abundance of local stone. Now many of the structures are damaged. The stone is decaying. Thanks in part to Irelands notoriously damp weather, these sites are in danger

发表于:2019-01-22 / 阅读(172) / 评论(0) 分类 自然百科2009年

Parenting on the move is all about sacrifice. And in the forests of northeastern Australia, another great journey spurred by parental dedication is about to begin. On translucent tawny wings, a little red flying fox flaps homeward after a night of in

发表于:2019-01-22 / 阅读(134) / 评论(0) 分类 自然百科2011年
学英语单词
acetabular index
age-specific mortality rate
Amfissa
Anemone polycarpa
angelicine
artificial seasoning
assequent
Avena nuda L.
Babinski's law
bakstone
be on your feet
beef to the heel s
blue cap
Calotropis
catsicle
cattle-lifters
characterization foctor
chemosensitizers
Chinese era
come out of retirement
creem
crystalloid osmotic pressure
cutter concrete pavement expansion joint
daunts
deenergized period
deformation compatibility condition
Domusnovas
double space mean
Double-headed arrow
dream tickets
drew number
El Oro, Prov.de
elliptical cross section
Esselenian
excusableness
exitance
five-pole separator
forked over
Forssa
four-gradient
fully engorged larva
generating gear
hadjeen
high water springs
hincty
homogeneous (and) isotropic random function
horn spacing
Human computer
Huntly
hydrogen leakage crash
income blanket
isobathye line
jxs
kaltmarinaden
Kosturino
Lamioside
letelier
main heading
maximum f-ratio
miniature induction motor
mnimh
multistory garage
negative differential
ocimenone
oneirodes pietschi
overladen
pailleur
penloaf
perjurest
piping work
plugging up
poison-tree
primary amebic meningo-encephalitis
pseudofluctuation
ratio of rotating speed difference
reannealing kinetics
Sapindoside
sateenwood
ship classed in A.B.
shipowner's lien
Shuwayy
single-pieces
speed on straight course
St George, Co.of
Stock Exchange of Singapore
stood out
strap on booster
structure of the hilum
substitution standard
Sutter Creek
teat sinus
toggle arrangement
tongue in chic
topologically complete
towai
transmission organ
vertical revolving arm mixer
walk of life
welfare members
wettstein
xerographic technique
zinc anode