时间:2018-12-27 作者:英语课 分类:英语时差8,16


英语课

Last time we talked about how astronauts eat and drink under weightless conditions in space.  


Today we'll cover the next question kids love to ask-how do astronauts go to the bathroom in space? It may sound silly, but it's really a good question, because weightlessness does make a visit to the latrine a tricky 1 proposition. 


Weightlessness poses two main problems in the bathroom. The first is that the astronaut could drift away from the bowl at any time. But there's a simple solution: they put on thigh 2 and foot restraints in order to go to the john! The second dilemma 3 is a bit more complicated. Here on earth, gravity assures that our waste falls downward, away from the body. But under weightless conditions, body waste has the disconcerting tendency to hover 4 close to wherever it exited the body. 


On the earliest space flights, astronauts had to tape a bag to their bodies to catch the waste. But that got pretty messy, so don't try it at home! Today, astronauts actually use flushing toilets-but the toilets flush with air, instead of water. First, the air flow draws the waste away from the body, then flushes it into storage tanks. All of the liquid waste from the spacecraft is stored together in a holding tank, which is periodically dumped overboard, where the liquid evaporates. Solid waste, on the other hand, goes into a container that's exposed to the vacuum of space. The vacuum completely dries out the solid waste, which is taken back to earth for disposal.  


 

1 tricky
adj.狡猾的,奸诈的;(工作等)棘手的,微妙的
  • I'm in a rather tricky position.Can you help me out?我的处境很棘手,你能帮我吗?
  • He avoided this tricky question and talked in generalities.他回避了这个非常微妙的问题,只做了个笼统的表述。
2 thigh
n.大腿;股骨
  • He is suffering from a strained thigh muscle.他的大腿肌肉拉伤了,疼得很。
  • The thigh bone is connected to the hip bone.股骨连着髋骨。
3 dilemma
n.困境,进退两难的局面
  • I am on the horns of a dilemma about the matter.这件事使我进退两难。
  • He was thrown into a dilemma.他陷入困境。
4 hover
vi.翱翔,盘旋;徘徊;彷徨,犹豫
  • You don't hover round the table.你不要围着桌子走来走去。
  • A plane is hover on our house.有一架飞机在我们的房子上盘旋。
学英语单词
acidophilic normoblast
amphosome
arbit-
bananivorous
Barrisdale
be roasted alive
befate
block convolution
breed fuel
brita
bumpety
by my fay
card system
cash shortfall
catapult into
cfdm(constant factor delta modulation)
cholagogues
ciliospora gelatinosa
color character display
compter-TV
cusp catastrophe
cypionates
data acquisition and display system
deep(er) bed
department economics
dermal tissue
discimpressor
disillusionizes
dizengoff
dodge the bullet
Duchemin's formula
ECELR
ectosomes
electromagnetic stored-energy welder
eudarluca caricis
eustacies
fensterwald
festinate
fjord shoreline
flurted
francias
fuel-saving technique
fundamental vibration-rotation region
get down to work
gin stand
hapticity
hazelton
heldreichii
hub sleeve
iodine separation
Kerber eyepiece
local strain
magnesium hydroxide
magnetic rotatory dispersion
mass etch
mecodium polyanthas copel.
Megalo(Magalo)
melanie
microcomputer based cassette recorder
misdefending
mode change-over disturbance
moot court
multi-tasking
multiple gangrene
pectus alare
phaseless
presenile dementias
primer handle
pygidial gland
quinidine gluconate
resbenzophenone
reticulated ashlar
rim slip test
ring coil
segment report
selective depressant
set sb at rest
shitfuls
slit card
small scale map
solid-jet injection system
souxite (varlamoffite)
splinter removal
stationary barrier
stetina
straight arms
suboptimal temperature
suhui
tare mass
tennis tournament
thawrtouer
tractor sweep
trimizoline
ttm
turbine-driven
UHF (ultra-high frequency)
underbid
Unterheinriet
vertical plane coupler
Westhaven
xenelasia
zofrans