沿层速度分析

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(83) / 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(113) / 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(86) / 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(75) / 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(78) / 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(95) / 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(103) / 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(105) / 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(76) / 评论(0) 分类 2016年NPR美国国家公共电台10月

This is the second in a 2-part Business English Pod series on presenting a SWOT analysis. A SWOT analysis is a tool that helps companies understand their strengths and weaknesses, while keeping in mind the opportunities and threats they face. In this

发表于:2018-12-31 / 阅读(155) / 评论(0) 分类 商务英语演讲课

In this Business English Pod lesson, we start the first in a 2-part series on presenting a SWOT analysis. A SWOT analysis is a simple but powerful framework for analyzing your companys strengths and weaknesses these are internal to the company as wel

发表于:2018-12-31 / 阅读(172) / 评论(0) 分类 商务英语演讲课

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(92) / 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(105) / 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(120) / 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(122) / 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(124) / 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(111) / 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(85) / 评论(0) 分类 2018年NPR美国国家公共电台4月

CLEVELAND, Jan. 9 (Xinhua) -- Cleveland Cavaliers' Brazilian center Anderson Varejao will be sidelined in the next two months after it was revealed he needs surgery on his right knee. Varejao suffered the injury during the Cavaliers' 113-99 defeat to

发表于:2019-02-18 / 阅读(117) / 评论(0) 分类 英语新闻
学英语单词
-morphic
allowable buckling unit stress
anecdotage
angle bisector
association of special libraries information bureau
automatic garden tractor
barbarigas
bibiana
bronchial gland
bronstone
brush and slotless motor
bube
cain
Cannabinaceae
CNPAC
cogwheel respiration
conceptual mode
deepwater pipefish
disbursable
domesdays
dow jones news/retrieval service
duck ass
duckiest
Embid de Ariza
esophageal, esophagal
Faiella
favo(u)rable wind
fleuve
frita
Friville-Escarbotin
full-height drive
glycerin enema
grand ensemble
graves
have no say in
hepatic injuries test outfit
hereditary canavan's disease
hirondelles
human-made
humeroradial
hypophosphoremia
interchangeable card feed
ischemic hypoxia
judgmentally
Karaagash
kasigau
knockkneed
lakeshia
lever unequalbeam balance
load bearing capacity
Matanza, I.
melt-back process
mictohaplonic (kniep 1928)
mode of excitation
moving period
multiattribute utility analysis
nakra fever
natural steatite
negative sequence field impedance
non-methane hydrocarbons
noncommutative operation
nuala
ogarkov
one-way clutch of hydrodynamic torque converter
optimum phase boundary
overboldly
oxalinast
Peorian
petticaptain
piriform fossae
postinfarction pericarditisxi
predefined specification
presbyopial glaucoma
presentence investigation
put someone out to pasture
railroad through transport
rapid formation
rate of both profits and taxes on entire funds
rearward perception
Rukungiri
Satadougou
Saussurea veitchiana
situational theory of leadership
splenic lymphonodules
submit to trial
summercaters
table driven compiler
thin-cut
tinsel conductor
tippence
top stack location
track supervisor
Triopac
turn-key contract
Turner Valley
turret-hatch race lock
unified type system
unpublished
variable-sweep aircraft
von Pirquet's test
water resources regionalization