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
ablatant
advice of delivery
airmass positioning indicator
American mucocutaneous leishmaniasis
as occasion demands
asota egens indica
audible test
automation of cargo handling
badger fur
Barowka
be designed to do sth
betamax tape
big vein
bijugate leaves
binderless briquetting
bituminous mortar flooring
blazonments
Bosangu
breakage or damage of axle
breeding population
bubble levels
caats
cam box
Campanula delavayi
car club
Cof.
coil-in-box cooler
cost and freight air port
counter-scale
current term settlement
cutting-vibrating combined machine
deepening finish
dendrolagus ursinus
Deparkin
derivative works
direct allocation of goods by the factory
dive in headfirst
driver bus
ensearing
epoxy-ester
error-dependency
final separator
flip angle
funeral services
G-30320
gold
Gursel
Ha Giang
headnet
hexylthiophenes
high voltage lamp
history-dependent control
Hoceima, Is.
horizon plane
infinitys
internally heated retort oven
isomenal
juvenuss
kinematic cosmology
knock-ups
line addressable RAM
listener-in
LWS process
mercurobutol
methyltryptophan
mmpa
nash theorem
Nicol's radiometer
nikkeis
not give two hoots for
Oberau
open shelter decker
paperbag rebreathing
pardonee
patent sheave
poretz
pressure-sensitivity
pull sb by the nose
pull-down current
radical surgery
rainy season construction
rejection sensitivity questionnaire (rsq)
rimboes
roper
rustpreventative
skited
slave owner
sleepsack
sode slip
start characteristic curve
strontium selenide
stylus (pl.styli)
subadditivity
Tea and Toast
tellian
tonalite-pegmatite
toxicoid
transceiving
Tricomicid
trigger circuit
tympanic intumescence
viewnet