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
an autograph
ATR switch
bidirectional replication
bird shots
burden
business model
C. P. Q.
calixtes
carbon black external surface area
computing equipment
contributiveness
cross current solvent extraction
cry quarter
days of examining and receiving
deacidite
deep absorption
degree of beating
diodes
direct strain
display principle
dot generators
dynamometamorphic deposit
end ordinate
endoscopic image guide bundles
energy transport
equalizing beam for counterweight
eukaryota
every hand
feedreader
fimo
flebile
generalized Ohm's law
ground sample
grow cold
Gulo luscus
hatch-rest sections
health report
holding capacity
HSTV-L
hydrogenwelding
hydrologic equilibrium
imbibings
kabat-zinn
Kilpua
latini juniani
Let me be your banker
lift ... hands
lightspeeds
longitudinal joint
Lophatherum and Gypsum Decoction
low hydrogen sodium electrode
lumen output
lusciousness
meteoric swarm
method engineering
monadal
multitoothed cutter
muskeget chan.
neonesidea taiwanensis
non-petroleums
noncumulative preferred stock
nontrinitarianism
Oklahoma City bombing
ostreaculture
papalagis
parisian-style
parock
parthenogenetic propagation
photo nadir
pitot tube method
Plectrovirus
polydisk
pornulation
preconcertedly
primacy effect
propeller guard
propyl acetoacetate
Propylamino
prostraters
protofascists
public procurator
recless
reversing-rolling mill
right ascension of mean sun
rotating converter
Saros Körfezi
scatterhoard
Songhai
specific speed of fan
spread of axles
swellingly
take a hold on oneself
third trimester of pregnancy
TSI (turbine supervisory instrument)
typhiss
unit clamp bolt
vacuum tuberculin
vasorrhaphy
vollenge
welded and rolled tube joint
whoself
ynckle