氧化层

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(81) / 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(108) / 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(84) / 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(74) / 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(76) / 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(92) / 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(100) / 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(103) / 评论(0) 分类 火星生命

By Katherine Cole Washington 31 July 2006 The lineup at this year's Grey Fox Bluegrass festival reads like a who's who of modern bluegrass: Grammy-winners Ricky Skaggs, Tim O'Brien, and Jerry Douglass all traveled to take part in the musical weekend

发表于:2018-12-16 / 阅读(144) / 评论(0) 分类 2006年VOA标准英语(七月)

'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(72) / 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(90) / 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(113) / 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(102) / 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(117) / 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(120) / 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(120) / 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(109) / 评论(0) 分类 火星生命

By Phuong Tran Dakar 14 February 2007 In Ivory Coast, lawyers for the victims of last August's toxic waste dumping incident say the millions of dollars a Dutch company offered the government Tuesday is not enough, and they will move forward with thei

发表于:2019-01-10 / 阅读(158) / 评论(0) 分类 2007年VOA标准英语(二月)

By Joe Bavier Abidjan 28 October 2006 More than two months after hundreds of thousands of liters of toxic waste were dumped in Ivory Coast's main city, a massive cleanup operation is nearing completion. Waste removal experts work to remove hazardous

发表于:2019-01-10 / 阅读(126) / 评论(0) 分类 2006年VOA标准英语(十月)

RACHEL MARTIN, HOST: Eight years ago today, an explosion on the Deepwater Horizon drilling rig killed 11 people and led to a massive oil spill in the Gulf of Mexico. The accident prompted big changes in how the country regulates offshore drilling. No

发表于:2019-01-16 / 阅读(82) / 评论(0) 分类 2018年NPR美国国家公共电台4月
学英语单词
a reversed charge
a-wilson
AGP slot
alagna
Alamicamba
Aldadine
audit budget
automatic start circuit
beddomei
Blera
blowre
boggify
browbones
Bucky rays
capacitance drift
carbonisation low temperature
central limit order book
charcuteries
chimed in with
clayey-silts
coking coal
cuisses
cuozzo
current record pointer
curved jaw
dissociated ammonia atmosphere
Douarnenez, B.de
double stitched seam
drug dose-response curve
dumping me
EAMA
earth-probing radar
electric lift truck
electric thermograph
embryo adoption
energy per mole
figure of merit (g/t) structure
Filarioidea
flaouna
flock in
Foiin-McEllroy's tests
formulated concentrate
fortitudinous
freight wharf
fundamental magnitude
genus prionotuss
glysters
hand-hold
homoians
Houttuynia cordata
incremate
infoliating
isooctanol
judaeas
kahuma
LEM,Lem
lines-of-battle
metal optics
monoseaplane
morphosyntaxes
multiple heat casting
musical passage
NAEB
Nereis marmorata
non-sovereigns
nonsigmoidal
old-soldiers
orthoclase nepheline syenite
overcarry
packaged dangerous goods
paratelepteris glanduligera (kze.) ching
phaeospora bambusae miyake et hara
pilot burners
pit deepening
plaguy, plaguey
polyhedrons
praescutata viperina
proctology
Rindal
route three-dimensional space design
SBCT
seah
shellpad
ship carrying dangerous goods
silver trevally
simple alopecia
slip toggle
sodium nitrite poisoning
statement bracket
statutory offenses
strombus vittatus
sugar-chest
sulfitation
sybra bioculata quadrinotata
tectonic deformation
term multiplicity
Theresa of Avila, Saint
torvizcons
transparency glaze
tritcs
underdevelopments
zigzag resistance unit