8) There is no doubt about other life existing in the universe. There are billions of galaxies in the universe, with trillions of stars in each one of the galaxies. And every one of those stars have planets orbiting around them. The chances that a planet is in the "Safe Zone," the distance from the sun that allows for liquid water to exist, is huge! We just have to find the planets that are in that safe zone. As for aliens visiting us, well that is up for debate.
I, for one, believe that they have visited us, and the governments *might* (as in there is a possiblity, but there is an equal chance that I could be wrong) be covering it up. The reason for that cover-up is something that I can't imagine. If there is a cover-up, then it is for national security. I don't know about you, but if I found out that aliens had visited us I know I wouldn't panic. In fact, I don't think that it would affect my lifestyle much, if any. I would think that it would be cool, but I would`nt go around looting because aliens had visited Earth.
There is a lot of proof that aliens have come to Earth, and it is not just people taking pictures of UFOs either. There are records from ancient civilizations that describe alien encounters. There is even a classical painting that shows something like a UFO. The artist (I forgot his name) even made the point of painting people pointing to it in the backround. All this evidence tells me that aliens have visited Earth.