I believe in aliens 100%, I mean if you study our planet and the way other stars have planets it's so obvoius, in our own solar system our planet's chemical makeup of their own atmospheres are so diverse these other stars with planets probably have a planet with a decent amount of oxygen and hydrogen in it, which would produce water. The reason we don't know planets with the ability to support life exsist is because we can only get very large gas planets to affect the movement of stars, an planet like earth doesn't have that big a gravitational pull. So yeah, I believe.