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
-EN, -REN plurals
Acamar
Aichwald
automatic advancing of printer page
barkors
be beyond a joke
beauty school
Blytt-Sernander climatic classification
calabash pipes
cap-shaped
chimney-climbing
commercy
congruent plan figures
coolheadedly
cremil
dead cat
disload
dubossaries
dysenteric malaria
equalitarianism and indiscriminate transfer of resources
ERBC
Eridu
ethyltriphenylsilane
flushing of pipeline
fossae lateral pharyngeal
fountain pen ink
fruit tree pathology
Gambian
geotropic root
global gain
Grφttavatn
gum erosion
gun propellant variable charge
helicopter deck landing devices
hierarchy of human needs theory
high melting point
houghteling
hudsonicus
hyphomycetoma
I don't want it
idle man hours
India canna
infective stricture of urethra
instarring
instrument autotransformer
intercapital veins
intermediate or interlobate moraine
jot down
lipofectamine
lymphosarcoma kundrat's
magnetic amplifier characteristic
mail transport office
method of measurement without contact
metulla
MicroDV
microsec life radioisotope
millicharges
Moneron, Ostrov
Moulouya, Oued
multirun
necker-chief
non-embrittling sulfur black dyes
occupants
offhandednesses
Opalinida
p-allylphenyl methyl ether
polycrystalline diamond
Postbank
preoperative embolization
prerennin
pretrite
pseudoconglomerate
racking type cooling bed
raised style
resin streak
role begin date/time
Ryō-zen
schaer
sea measurements
seasickness bag
semireligious
shoalest
singing of repeater
single-surfaced
skinny
Steinem, Gloria
suspend disbelief
suspension center
syringa spp
telepherage
theta roles
this day and age
total residence time
universal trocar
vee trough
venae dorsales penis superficiales
virus safe
visual literacy
work in hand
work relief
Works for me.
yoicking