SPACE is a lonely place. Hundreds of thousands of kilometers from home, astronauts have a hard life. It stands to reason that, once in a while, they need to have a good cry. But this is a lot harder than it sounds. We still know very little about space, and about living in zero gravity. In fact, we are discovering new things every time astronauts take to the skies (and beyond). As The Atlantic reported in January, crying is not all that simple in space. This is because when a person normally cries,  gravity makes their tears move downwards. But in a spacecraft, this is not the case. Here, there is no gravity, which is why we so often see pictures of astronauts floating around. This means that, strangely, when you cry your tears have nowhere to go. As a result, they just stick to your eyes. In May 2011, astronaut Andrew Feustel experienced this. "Tears," as he said, "don't fall off your eye... they just kind of stay there. " This can be quite painful. In space, your eyes get very dry, and the added moisture is irritating  . Sometimes, things get even weirder . The astronaut Ron Parise told The Atlantic that when tears get big enough, they "break free of the eye and float around". No one can be quite sure why we cry. Why should water in our eyes have anything to do with feeling sad? If you stop to think about it, crying is a very strange thing indeed. And now, thanks to the wonders of space, it just got even stranger. Astronauts feel  _  if tears are always in their eyes.
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