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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(133) / 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(156) / 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(124) / 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(116) / 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(113) / 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(142) / 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(152) / 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(142) / 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(117) / 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(133) / 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(149) / 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(141) / 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(164) / 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(171) / 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(168) / 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(155) / 评论(0) 分类 火星生命

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(142) / 评论(0) 分类 2018年NPR美国国家公共电台4月

By Naomi Martig Hong Kong 28 November 2007 Japan's upper house of parliament has approved a bill that would stop the country's air force transport mission in Iraq. It is the latest clash between the opposition party and the government over Japan's ro

发表于:2019-01-31 / 阅读(117) / 评论(0) 分类 VOA常速英语2007年(十一月)

今天我们要学的习惯用语有共同的关键词: lip。大家都知道lip是嘴唇。嘴唇可是我们身上忙碌的器官,我们说话,吃喝都得靠嘴唇帮忙。嘴唇还帮我们传情达意。难怪由lip这个词发展而来的习惯

发表于:2019-02-12 / 阅读(171) / 评论(0) 分类 美国习惯用语

CAIRO, Jan. 29 (Xinhua) -- The polling stations of Egypt's Shura Council (upper house of parliament) elections closed Sunday on the first day of the two-day vote with a low turnout rate of voters. In the first stage of the upper house elections, vote

发表于:2019-02-18 / 阅读(126) / 评论(0) 分类 英语新闻
学英语单词
absolute rent
Alfedena
alkaline medium
American Academy of Forensic Sciences
amorphous sky
biosafety level
blown mineral oil
body-seat
bromouridine
calhaus
catch-alls
categorical grants aid
cenosphere
centi-cycle
chain feature
cheesecake
classification of expenditure
Clostridium tetani
conradson carbon test
corporate entrepreneurship
cotrees
dead voltage
desert lagoon
die blank
disk-and-drum turbine
dust-arrester installation
dynamoelectric motor (dynamotor)
electron helix
elucidation of facts
emotional music
energy-conversion
equilibrium density centrifugation
evps
flocculonodular lobe
fnlas
fuke
Gehennom
global-level
hegemonised
ictus fulminis
insect aerosol
isolationism
isoperistaltic anastomosis
joke poach
kategaya
keep regular hours
Kidepo V.
level area
location free procedure
Lophomonadina
LPC
Lufty
lymphopathy
main stop valve
maricella
maritime work
master file index
minidressed
mxb
Narnaul
neurodermitis
no-war
nonlinear optical effect
occupied population
once a year
once-glaze ware
optimization model
organic amnesia
out on the tiles
overchoreographing
oxidation state
parforme
peer groups
phenolic acid resistance paint
photoflavins
plagiaries
pulsed extraction
red-sensitive cell
restructuring operation
ribofuranosyladenine
semi cubical
seraphin
sertofren
service staffs
session level function
seven layer model
silver foil
Sombrero, I.
spank it
spherelike
squeezing and pressing method
supergroup filter
suprarenalectomies
t and o maps
ta t'iao
technology-related anxiety
triquinoyl
TVWS
uncovetingly
uranium sulfide
ventricular function curve
wire mesh chicken floor