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
2-propanone
all-trades
Amalphitan Code
arithmetic underflow
backsies
brises-soleil
broda
buttress-root
captive firing
cathode-biased flip-flop
change-manager
clinocephalism
Control character.
coupling knuckle pin
cutawi machine
d.v
dbrc data-sharing control
dentin matrix
devotional
distractingly
dual indicator
efficiency of feedlot gain
endorsors
Fastnachtsspiel
Fintona
fluorophytosterol
give something one's best shot
glass resistor
glossolysis
gorilla gorilla beringeis
herocane
high quality training
ICP (integrated circuit package)
in a string
ink surface tension
joint variation
K'elafo
kindredship
lace
lignum benedictum
made myself understood
mamma's
marchandise
Marmesine
mattlis
menemsha
minieres
minocycline
molecular radius
multiplicative variation
nazarbaev
o-aminophenol sulfate
oulette
perthiocyanogen
pettitts
Philos. Rev.
photoplastic recording
plain friction bearing
PNAB
polyamorist
polysaccharoses
population gradation
postburnout heat transfer
prefield
pseudohibernation
Pulvinaria camellicola
scenopinids
sectoral supporting services
self-convergent CRT
several-seeded
showing over
side reaction coefficient
silicon planet
smilesmirk
soft switching
solid rolled centre
spark plug pliers
spoon feed
St. Johns River
starus
stepped arch
stern tube packing gland
stoker coal
straight low
subsea template
subsequent settlement
Sulci cerebrales
systemic herbicide
tall drink of water
Tang ware
Tawfīqīyah
theorem of polyhedron
thethy
thousand-years
threatening question
tibetan terriers
tonalpohualli
transliterates
wakon
wave penetration
Weber-number
worthly