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Conditions on Mars were so harsh that it was hard to imagine any life surviving there. The idea of sophisticated aliens was wiped out. We know that conditions on Mars today are not very good for life.

发表于:2018-12-07 / 阅读(125) / 评论(0) 分类 火星生命

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(151) / 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(120) / 评论(0) 分类 火星生命

In 2001 a new NASA probe was launched. Called Odyssey, it was sent to Mars to carry out the most detailed analysis ever of the planet’s surface. What it has discovered may be about to answer one of

发表于:2018-12-07 / 阅读(113) / 评论(0) 分类 火星生命

But even if there had been water, life doesn't start overnight. Even a simple microbe is the product of complex chemical systems that take millions of years to evolve. Had the water lasted long enough

发表于:2018-12-07 / 阅读(108) / 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(134) / 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(140) / 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(137) / 评论(0) 分类 火星生命

'Deepwater Horizon' Honors The Sacrifice Without Sacrificing The Action play pause stop mute unmute max volume 00:0003:02repeat repeat off Update Required To play the media you will need to either update your browser to a recent version or update you

发表于:2018-12-18 / 阅读(108) / 评论(0) 分类 2016年NPR美国国家公共电台10月

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(125) / 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(142) / 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(136) / 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(155) / 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(162) / 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(158) / 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(151) / 评论(0) 分类 火星生命

BEIJING, Feb. 5 (Xinhua) -- China on Tuesday unveiled reform guidelines on income distribution amid growing public concerns over a widening wealth gap. The guidelines encourage further work to improve the initial distribution system and stepped-up ef

发表于:2019-02-03 / 阅读(127) / 评论(0) 分类 英语新闻

The men take everything, but the women -- nothing -- Camp resident Rosemonde Desmesier Residents of makeshift tent cities throughout Port-au-Prince say that conditions have improved since the earthquake three weeks ago, but shortages of food and reli

发表于:2019-02-03 / 阅读(160) / 评论(0) 分类 VOA标准英语2010年(二月)

By Lisa Schlein Geneva 21 August 2007 United Nations aid agencies say the distribution of humanitarian assistance to victims of Peru's devastating earthquake remains problematic. But they say the situation is beginning to ease. Lisa Schlein reports f

发表于:2019-02-03 / 阅读(204) / 评论(0) 分类 2007年VOA标准英语(八月)

BEIJING, July 11 (Xinhua) -- The State Council, or China's Cabinet, announced on Wednesday that it will boost the development of the nation's distribution industry with the goal of establishing a modern goods distribution system that is efficient, co

发表于:2019-02-08 / 阅读(152) / 评论(0) 分类 英语新闻
学英语单词
adaptee
alee
amb oil
animalculous
annular vessel
asbestos filter cloth
asplenium trichomanes l.
Bandakagni-Sokoura
basic bore
best estimate
beta contamination
Bethisy-St-Pierre
bfhr
bimetal lamp
Bott.
bottom kill
Buchan G.
business loans
career criminals
cell metabolism
cohomology module
compressed gap
contrest
cosmic flight
cost accounting analysis
cruelerer
crystallographic symmetry
current fraction of the ion B
declaration of dividends
depoliticisations
dermatomycin
deuin
echo studio
electrochemical gradient
enterprise network
Eutamias asiaticus Gmel.
exhib
familly
federal public-key infrastructure
fill band
fundamental-unit
funded income
gallnut
gastropine
Graeffe's method
heavy-duty rudder
heterochromatinization
homogeneous condition
Honokawa
horizonally-polarized wave
hot melt adhesive edge bander
hypodipsia
in-centre
increase of charge
industrial bacteriology
instead
international search
Irish pennants
Katayama
least mechanical equivalent of light
linear pinch
link mechanism
LOCIS
low-warp-looms
malherbe's benign calcifying epithelioma
megacases
metafile
metatrophic intracavitary
monocell
non suspendable subsystem
nrp
or-as
paijenborchella iocosa
parish-hadley
Picard group
planing form
plexin
Polish Register
presift
principal determinant
programmed society
push-pull rectifier
quenching medium
receptivities
recovery parachute
rosca
Sakae
Sir Bernard Williams
sleeper renewal
soft-lefts
sphericities
Suifenhe
tailstock clamp bolt
three dimensional picture
toca
tomato pulp
uninspirable
valonias
venter
verification by consent
water insoluble cutting oil
weight-to-yield ratio