阅读理解
Being an astronaut sounds cool, doesn't
it? In space, they get to do some pretty amazing things, like floating (漂浮) in zero gravity(重力).
However, there are also plenty of things
that astronauts can't do because of their weightless environment(环境), and that's very
sad. What's worse, they can't even let their sadness show -because it's
impossible to cry in zero gravity.
Of course, astronauts can still produce
tears. But crying is much more difficult in space, reported The Atlantic in January. Without gravity;tears don't flow
downward out of the eyes like they do here on Earth. This means that when you
cry in space, your tears have nowhere to go — they just stick to your eyes.
In May 2011, astronaut Andrew Feustel
experienced this during one of his spacewalks. "Tears," he said,
"don't fall off your eye...They just kind of stay there."
Besides making your vision(视觉) unclear, this can
also cause physical pain. Back on Earth, tears are supposed to bring comfort to
the eyes. But that's not the case in space. The space environment dries out
astronauts' eyes, and when tears suddenly wet the eyes, it can cause pain
rather than comfort. "My right eye is painful like crazy." Feustel
told his teammate during the walk.
Since gravity doesn't work in space,
astronauts need some extra help to get rid of the tears. Feustel chose to rub
his eyes against his helmet to wipe the tears away. Another choice is to just
wait — "When the tears get big enough they simply break free of the eye
and float around," astronaut Ron Parise told The Atlantic.
There are lots of small things — things
like crying — that we are so used to on Earth, we usually take them for
granted, until they become a problem in a totally different environment, like
space. There, astronauts can't talk to each other directly. They also can't eat
or drink in normal ways. They can't even burp (打嗝), because there is no gravity to hold
the food down in their stomach. If they do burp, they just end up throwing up (呕吐) everything in their stomach, according to the UK National Space
Center.
Thus, perhaps it's only space explorers who
can honestly say, "Gravity, you're the best."