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If I were an alien looking for a new home, I think I would try a few million of my neighboring planets before bothering to travel a hundred thousand trillion miles to visit the Earth, in a journey that would take at least 200,000 years. But what about all those UFO sightings that are reported every year? Well, most of them are planes. And whatever the others are, they're not flying saucers. If you were a visiting alien with incredibly powerful technology, what would you do: hide yourself away and keep quiet, or land and take over the Earth? I know what my answer would be. If there are other forms of life elsewhere in the universe and I'm sure there are, that's exactly where they are – elsewhere.