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
adhesive wear
air conditioning module
antiklystron
antispastic
arjan
assembl? dessus
auxiliary control source
Bacillus fragilis
basic trainings
Battle of Kerbala
branching program
by-matter
cantharophily
cargo tank boundary
catalog system
clans
Coblenzian stage
cod (chemical oxygen demand)
cold-drawn appearance
composicion
content portion
decomposition rule of functional dependencies
dicop
direction of growth
Dymnamic Host Configuation Protocol
ecquaintances
edulcorates
everly
explorative
extended hypergeometric function
ficklest
flat chisel
full-service merchandiser
goycochea
height of cut and fill at center stake
hepatologic
immigrants
immune hemagglutination
in presence
interinfluence
intermundial
inverter module
isoparametric finite element
Jorgenson's rational distributed lag
legal matters
mavel
mixdown
multimicroelectrode
myomatosis
non-centralize control system
noordzeekanaal (north sea can.)
nuclear Lie group
optical digits-display
overlusty
ovipositions
pandarous
Pastafarians
Paymogo
plastic ware
platycephalic
population education
prontalo
Queen's Club
Radiobacter
red shirts
reinfuse
release shackle
resource leveling
retouching
rightsholders
roosting
Ros'
rural domestic waste
sanjakate
sano
sea nettles
sea-captain
secrists
semi-pros
set speech
sgi
soetebier
soldering-iron
sponsorings
spotted fevers
supersentence
suricats
Tang ware
the appearance
the wash
thick films
tianqiao
ticklier
tranquilizes
tweendeck ship
twerps
unbesound
under the plow
vertical drying machine
vessel head shipping skid
vibrissina angustifrons