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
acid-etching
alden-hebron
aluminium armature
at-once-payment
be toxic to many plants
beet leafhopper
blackway
bluest
Boise County
bolivianos
Bratolyubovka
broken off with
centimeter-wave device
chancroidal
chest press
China-watch
Chinese peony
Chingoroi
citraturic
clo.
combustion synthesis
community relation
conus praecellens
cotton bolls
cultivated parsnips
decernable
demotic scripts
dendritic(al) crystal
eccentric pendulum
end cooling
express car
firedamp explosion
fraudulent misregistration
frontierswoman
fruit of one's loins
gelatinising
high-vacuum evaporation technique
hot-temperature zone
hyracoid
i'art
interjectively
internal airline
intersectoral
Issa
karaikal (karikal)
konovsky
lateral lacunar lymph node
Ldls
Leontopodium artemisiifolium
leopard flower
linearism
log-log model
lose your job
low-porosity
maternity rights
maximum issue
muscle spasm
nitrification in soil
numerical score
Nurhachi
obats
odorotrioside
oraferon
paridrosis
patricians
pericolitis sinistra
petiolus cartilaginis epiglottidis
photo booths
physical connectivity
plaster match
platform-specific
polynomial modulation
pontile hemiplegia
pornophobes
presettable i/o conditions
quadrocopters
Queige
radio-frequency range
rate of premium
realityengine
San Cristobal, Mt.
scottish lallanss
semi-circular drain
simple goiter
sole leather
spring offset
St-Chaptes
starting air manifold
stepwise dissociation
sure-handedness
symbol manipulationlanguage
thorium picrate
Ti-n-Ouadine
token moneys
transvenom
triumphalistically
true laterite
tsutsumu
umbrages
wampee
wbf
wide opening,wide market