共用题干 Motion Sickness

Living in space looks like lots of fun.You can do certain things in space(like floating
around,or pushing huge objects)that you cannot do on earth.But being in space can do
things to you,too.If you stay too long in a gravity-free environment,your bones could
become weak,and a small spaceship just might annoy you after a while,because space
travel could make you seasick!
On July 4, 1982,after seven days orbiting the earth,astronauts Thomas K. Mattingly
and Henry W. Hartsfield returned home.Although not all of the experiments on board
worked properly,the flight basically seemed to be a success except for one"little"thing:
early in the flight,astronaut Hartsfield became"seasick".
Thomas Mattingly,who is also a jet pilot and is highly resistant to motion sickness on
earth,did much better.Mattingly sailed through space with a steady stomach.But no one
knows why Hartsfield felt uneasy and Mattingly did not.
So far it seems there is no reliable way to predict who will become motion sick in
outer space and who will not.In all,at least four astronauts have suffered from space
motion sickness. Russian and American scientists are working together to try to
understand and solve the motion sickness.Space program officials worry that if so
many highly-trained pilots get sick in space,what will happen when civilians start flying
in the shuttle?
Motion sickness is a disagreeable feeling that comes from the pitching,rolling,
swaying,or just the moving of the object you are riding in or on.Symptoms of motion
sickness include:dizziness,headache,a sinking feeling in the stomach,and vomiting
（呕吐）.
Why does motion make some people ill?
Doctors believe that motion sickness is caused by a disturbance in the inner ear.Our
ears do more than give us hearing.A part of the ears gives us a sense of balance and helps
make us aware of whether we are right side up or upside down.
If you know that you get carsick or seasick,what can you do?
Speak to your doctor. There are certain medicines available that can help stop that
uneasy feeling.But many of them can also make you sleepy.Usually they work best taken
before you begin feeling ill.
Some people also recommend water,ice cubes,mints,or plain toast.But these
remedies do not always work for everyone.
Perhaps,since motion sickness is such a big problem in outer space,researchers
may soon find a way to cure the astronauts一and those of us who stay on earth. Untrained civilians are more likely to suffer from motion sickness in a spacecraft.