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
'Afrīn
abdominal comb
aerial radiation pattern
Akhnoor
alphitobius diaperinus
apurimac
back-up device
beam-coupling coefficient
better round
BioBreeding
biocassava
biometric
Castlepoint
caucci
chunklet
cicatrizing enteritis
circle side shift device
clinical application
cojuror
concurrent operation control
cono
copper colors
die-cutting machine
diffusing source
DivX HD
domestic market price
dotson
draft flue
dynamo stator core automatic welder
emergency conditions
engine timing case
equatorial wave disturbance
erotic
feibai
fishbone cracking test
flashlight batteries
flaying machine
foreslope
gas-dynamic behavio(u)r
growth hormone
hand-engraveds
hemagglutinating-unit
hematic crisis
hyracodontid
inapparency
inexpediencies
intere
iron pyroarsenite
Jaculus jaculus
Khvormuj
lagenae
lantern halyard
Linthicum Heights
liquidation company
long pause
mama grizzlies
masking-out
methyl-tryptophane
mickeys
miswanting
netherley
newfig
Nicotiana L.
night flower
operation panel
orbitelous
oxyhornblende (basaltic hornblende)
pacific angel shark
paper chromatographic scanner
peripheral plotters
Phyllocladus asplenifolius
physical evaluation
physical keyboard
pituitary posterior
propylenglycol
pseudozoogloea
purchasing power of money
quaker-oats look
register glass
retorting amalgam
Risley
rolling wave
row median
sampled-data computer
shenge
shitweasel
source plasma
submarine mining
switch point guard rail
talk sb into sth
the beautiful
the school year
three-decked
time dependent method
toll enrichment
Tourette's syndrome
universally acknowledged
vacuum truck
vertical aerial photography
wet ground mica
with profit
written resignation