时间:2019-02-03 作者:英语课 分类:自然百科2012年


英语课

 A test run before attempting the fuel hungry and risky 1 trip to the planet below. 


 
Dreaming about Mars 2 and actually going there are two very different things. Mars may be our neighbour, but 35 million miles to the closest point is still a very long way from home. 
 
To put him on the surface of Mars, someone once joked there're only three issues: getting them there, keeping them alive while they are there and getting them back.
 
Our space age dreams of off-world colonies on the moon and Mars faded with the cancellation 3 of the Apollo Program and the last trip to the lunar surface in 1972. It didn't stop us from travelling, we simply switched from astronauts to lower cost, lower risk robotic explores. And when it comes to Mars, it's probably just as well. 
 
Getting to Mars is just unbelievably hard. We've learned that the hard way before certainly it gave to go back to the days before the rovers launch two third in the missions that they fall in the Mars and fail. They fail for all kinds of reasons: rockets that blew up and spacecraft that just vanished partly without a trace.
 
Five, four, three, two, one, engine start.. Lift off.
 
If you are ever lucky enough to book a flight on the first rocket to the red planet, you'd better be sure you've packed everything. The one-way trip is at least six months with no turning back if you've forgotten something. 
 
We can go to the moon and get back in a week. It takes about three years to go to Mars and come back. You have to carry your food, you have to recycle your breathing oxygen and your water. So it's a very, very major undertake. Within about three days, your earth looks very small. And within a week, it's just another star. And you suddenly are going to realize you are in very deep space and it can be a long time before you can go back.

adj.有风险的,冒险的
  • It may be risky but we will chance it anyhow.这可能有危险,但我们无论如何要冒一冒险。
  • He is well aware how risky this investment is.他心里对这项投资的风险十分清楚。
n.火星,战争
  • As of now we don't know much about Mars.目前我们对火星还知之甚少。
  • He contended that there must be life on Mars.他坚信火星上面一定有生物。
n.删除,取消
  • Heavy seas can cause cancellation of ferry services.海上风浪太大,可能须要取消渡轮服务。
  • Her cancellation of her trip to Paris upset our plan.她取消了巴黎之行打乱了我们的计划。
学英语单词
abc warfare
acid free paper
alkenyl group
anterior horn
aridelus antennatus
attolitre
aunti
bloodleaf
boom latch
capsuler
catoptric lens
cellulin
Chinese Academy of Sciences
clearing heat and freeing strangury
climate monitoring
clipper-built
coaxial shaft
Cockspur Island
colonal
composite head
congruence method
coulises
country dancings
DBIC
Denali
diplomatic rank
domelike structure
double sampling
electro-neutrality
electromagnetic wave scattering
emulsifying reducer
enorchia
evening paper
exon
fault clearance
fearing
field-line annihilation
forged integral rotor
forpassed
fourragere
galactopyretus
gating time
genus Geoffroea
gloeophyllum abietinum
goliath
goncalo alvess
grant a patent right
grapnel traveling crane
gyrosigma wormleyi
handbooking
Hangklip, Kaap
has a hard job to
hematoma of penis
hexyl resorcinol
high obstruction
hobb
in one way
invoice book outwards
ion transmission technique
iterative modeling
kimmich
land cover classification
leakage end
Leptochilichthyinae
lifeguard submarine
loom width
marconi operator
marline clad wire rope
merphyllin
modus operandi
mortal injury
Moréac
muharrem
near fields
network access machine
new world coral snakes
NF (Normes Francaises)
oligopsony price
orthoarsenate
postocellar bristles
practise law
pressductor
pseudo-pore
pyrorefining
rational grammar
reserve position in the fund
rotary-range mechanism
rotor axis
slag blanket
split chase mo(u)ld split(ting) chase mo(u)ld
stealth abs
stellar magnitude
sub-cavitation
sumra
T-1384
t-account
tenthredo esakii
testa trionidis
Tintange
titracen
two-dimensional paper chromatography
upper most position