UFOs are 'Unidentified Flying Objects' and I have seen quite a few of these in my lifetime. But they were 'unidentified' simply because I didn't bother to take the time to figure out what they were. If the question is whether I believe in 'flying saucers', my answer is no, I do not believe there is any physical evidence that we are being visited by extraterrestrials. If you want me to believe something as profound as that, you better show me some hard evidence at least as good as what I routinely demand in my daily researches on other astronomical issues which are hardly as important as the issue of whether aliens are visiting us. I don't care how many anecdotes you show me about people seeing things in the sky they don't understand. Between the US Air Force, fireballs, weather balloons and reentering space debris, there is a lot happening up there that can easily fool people.