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call，possible，send，different，get，close，might，although，large，discover |
Lots of scientists believe there's life on other planets．Because of this，they keep doing research about the universe．They have sent astronauts to the moon．And they have the answer．There's no life on the moon．Not long ago they spaceships to Mars．There，they didn't find life．And they found the environment of Mars was from that of the earth．Then they knew it wasfor people to live on Mars．
they haven't received a message from other planets，they believe their idea is right．Recently they have a planet．It's Proxima Centauri．It's very to our earth．It is just over four light years away．Proxima Centauri is than the earth．And there's water on this planet．That mean that life is possible there．Now scientists are studying this planet．Soon they will tell people the answer．
