单词：leached horizon
单词：leached horizon 相关文章
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
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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.
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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
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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
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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
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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
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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
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The rescue Flora heard somebody shouting. She looked around and saw Jeff running. Befor she could move,she heard a loud noise which grew to a terrible roar. She looked at Jell, who was waving his arms. She was so surprised that she couldn't move. She
高中英语人教版第一册课本听力
Many people remember the colors of the rainbow by the acronym ROY G. BIV. For red, orange, yellow, green, blue, indigo and violet. Well, the color indigo just made news. Indigo gets its name from the plant Indigofera tinctoria and its relatives, whic
2016年Scientific American(九)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
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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
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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
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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
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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
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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
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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'
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He wears gloves and cleans his tools with alcohol to avoid contaminating the ancient salt samples with modern microorganisms.
寻访外星人
the rescue Flora heard somebody shouting. She looked around and saw Jeff running. Befor she could move,she heard a loud noise which grew to a terrible roar. She looked at Jell, who was waving his arms. She was so surprised that she couldn't move. She
高中英语听力人教版第一册
AUDIE CORNISH, HOST: It's been two years since the peak of the drinking water crisis in Flint, Mich. The state has spent more than $16 million to distribute free bottled water to residents. That program ends this week even as some residents say they
2018年NPR美国国家公共电台4月
Don: Hey, Yael, Have you heard? We've discovered two new oceans? Yael: Where? D: On Mars. Well, they aren't there any longer, but they were there a few billion years ago. Y: I thought scientists weren't sure if Mars had oceans or not. D: They weren't
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