Thoughts About Aliens

After reading part The Falling Star, it makes me think about whether the aliens exist or not. I personally believe that there are other creatures exist on the other planets, but I do not think that they have visited our earth. I have seen those pictures that people took of the UFOs or the aliens, but I do not think they are real. We human beings have been curious about the outer space for decades, and movie directors also attempted to create aliens or outer space. Avatar by James Cameron is a good example. The people there live a tribe-life. Their quality of living is poor, but their brains are much well built. Even though this is only created by human beings, it is worth concerning. Should we just stay where we are, or should we be the positive side and go invade the outer space, or cooperate with them.