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
231
absitively posolutely
all goes down gutter-lane
all published
assimilatory quotient
authentic cadence
be enthroned in the hearts
benzyl acrylate
biogenic graded bedding
brogue
buying group
career pathing(CP)
cartelisation
Castejon
cellular organelle
chemigroundwood
Cheyenne River Indian Reservation
close epiphytotic disease
close inbreeding
Colima
Cornell-Coxe test
cross-blocking thinning
crosscurrent extraction
cultural resource management
curtilage
eccentric band
electrically actuated convertible top
electrolytic recording paper
Eurofascism
export commission
extraductal
family-owned company
filling block
fixed sole oven
Flensborg
forevermores
frettage
from the housetops
frontier traffic
further standard function
general chamber of commerce
get the drop on sb.
globall
help file name
hydrosoluble
illuminor
in spite of someone's nose
Inf.
inspection and acceptance
Jadelot's signs
kayans
left-hand helical gear
light button
ling hsing wu
low life
mailing address
make-up water pump
mandler
master-screw
mirandina corticola
modern game
MODSS
oil transformer
Ophiorrhiziphyllon macrobotryum
Oued Tinn
pattern plate bolster
perforation density
phonon-terminated laser
pre-digested
process queue
pulverizer
push poll
re-enabling
recanter
refresher driving
retaining possession
safety platform
saltern
savings certificate
sea crawfish
self tipping skip
semeterrie
Seminole Wars
settling
sheva
side-by-side reactions
sponge-iron
substitute t-ratio
substratum for waterproofing
symbol concatenation
Synotis longipes
time-switches
trait by treatment interaction
transfer data record
treble
true yellow
Tyrian purple
underdrain of filter
unfrilly
untuckered
W star
warlessness