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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(198) / 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(217) / 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(204) / 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(182) / 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(180) / 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(232) / 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(235) / 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(209) / 评论(0) 分类 火星生命

By Mario Ritter Broadcast: July 8, 2003 This is Steve Ember with the VOA Special English Agriculture Report. Recently, a listener in Nigeria told us about an organization called World-Wide Opportuniti

发表于:2018-12-07 / 阅读(216) / 评论(0) 分类 VOA2003(下)-农业与经济

From NPR News in Washington, I'm Lakshmi Singh. BP is coming under mounting pressure to step up its response to the country's worst ever oil spills in the Gulf of Mexico. It's coming down from top Obama administration officials who've been dispatched

发表于:2018-12-17 / 阅读(213) / 评论(0) 分类 2010年NPR美国国家公共电台5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(207) / 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(235) / 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(202) / 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(242) / 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(262) / 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(224) / 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(222) / 评论(0) 分类 火星生命

This is Scientific American's 60-Second Science. I'm Cynthia Graber. Thisll just take a minute. Bisphenol A. Also called BPA, it's used to make shatter-proof plastic known as polycarbonate, found in everything from water bottles to medical devices to

发表于:2019-01-08 / 阅读(243) / 评论(0) 分类 Scientific American(五)月

今天我们要学的词是organic。 Organic, 有机的,绿色的。 Organic product, 有机产品。近年来,美国很多消费者开始崇尚绿色、有机食品。不过,统计数字显示, Organic food accounted for only 3.5% of the fo

发表于:2019-01-11 / 阅读(203) / 评论(0) 分类 英语每日一词

A Smooth Wake 平静的尾流 (A smooth wake on today's moments of science) Female: Donne and I are on a fantacy cruise . The sun has set and were standing on the rear deck. Look at the reflection of the moon. Male: You might expect a ship's wake

发表于:2019-01-26 / 阅读(136) / 评论(0) 分类 英语听力文摘 English Digest
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aerotire
Alcmaeon
all way guidance
antiparamilitary
armesine
as happy as a sand boy
back dump
become a prey to
bioclimosequence
bridge loop
Brossasco
building ways
calabi-yau
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catalyst inventory
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crystallize out
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decennium
despumate
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dubok
family oleandraceaes
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golden marguerite
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horng
housej property management
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hydrographic reconaissance
hypertonic bladder
in the corner
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keyboard interface
klontz
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laka (hawaii)
laugh someone out of
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lower plants
miscellanea
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neoperla klapaleki
nullary
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paderewskis
parking ground
partial autocorrelation coefficient
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Pneumatic trough
pseudothallus
sails through
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secondary moment norm
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shell of boiler
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