土壤发生层

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(138) / 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(161) / 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(134) / 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(124) / 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(122) / 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(156) / 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(160) / 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(148) / 评论(0) 分类 火星生命

By Gary Garriott Broadcast: July 29, 2003 This is Bill White with the VOA Special English Agriculture Report. Soil conservation efforts protect soil from wind and water that can blow or wash it away.

发表于:2018-12-07 / 阅读(157) / 评论(0) 分类 VOA2003(下)-农业与经济

'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(124) / 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(140) / 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(160) / 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(148) / 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(169) / 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(179) / 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(173) / 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(161) / 评论(0) 分类 火星生命

Mars Rover to Begin Taking Soil Samples This Week Jessica Berman NASA engineers say the Mars rover will begin taking its first soil samples as soon as it departs the landing platform . Engineers say t

发表于:2019-01-04 / 阅读(167) / 评论(0) 分类 VOA2004(上)--各类新闻

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(149) / 评论(0) 分类 2018年NPR美国国家公共电台4月

time will not stand still today is the day, the day of salvation living for more than just synthetic force fed existence this is my disposition I will strive for the truth time will not stand still today is the day, the day of salvation living for mo

发表于:2019-03-02 / 阅读(178) / 评论(0) 分类 英文摇滚歌曲
学英语单词
Aaron's-beards
ad colligeqdum bona defuncti
allis diagram
anchor primer
anteroposterior facial dysplasia
applied radiobiology
armourbearer
assenter
auto-electronic emission
Background Repagination
be bail for
buffer asynchronous communication
carburettors
card read-punch unit
caridean
casualty of railway man
central granule
centrifugal screw pump
chronic meningoencephalitis
clued-up
consolidated-undrained shear
consul r.
control sphere
crank-case
delphintum hensyi french.
direction-finder antenna
discrete symmetry
dounk
electric powered chain saw
enclosed starter
ethercuffs
exactitudes
fellow countrymen
flavanonol
fuck-off
fuming furnace
genus antilopes
ghetto cattle
ghost knifefishes
giardina
globuli cell
half-order theorem
high frequency pulse generator
HKDD
idioecology(autecology)
internal core
laboratory report
ledgers
Leontopodium pusillum
light silty loam
linstocks
Los Aldamas
lower main shield(ing)
magnetic stratigraphy
magniophilite (beusie)
make a progress report on a project
memory allotment
method of dependence
microcosmical
military-school
milk-can
mirabeaux
mode extension
monoclinic prismatic class
multiple hurdle
mycobacigdin
N-formylglycinamidine ribotide
neonesidea expansa
nonorderly
omnificent
paratectonic
phoneplex telegraph phenetics
quasi-probability
retrieval algorithm
ripping dirt
rubber sleeve
sack paper
San Miguel del Monte
scarabaeidaes
scipper
screwed pipe joint
scrutineer
side-lateral
single traction
sonorization
sour citron
student-built
Sālang, Kōtal-e
take ... on faith
take the mickey out of someone
three color traffic light
thyrotrope
tip extrusion
total condition
translucent mosaic
uk fund
ulent
unbalanced error
vectoring doctrine
volatile organic carbon
voltage-reference tube
whiptail lizard