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Skip this UFO report...Week of February 23, 1998It's not too often I can merge my Bad Astronomy with the snacks, but last night I saw something that combines them quite well. The Discovery Channel, which really should know better, aired a show about UFO's. This may surprise most folks, but I actually have an open mind about that issue; I just haven't seen anything really convincing yet. Interesting, yes; convincing, no. Most of what I have seen has been misidentification, aided by most people's lack of knowledge about the sky. So on this TV show, the name of which I unfortunately didn't catch, they had a short blurb about an object that was spotted by a US spy satellite some years ago. The object came in from outer space, went through our atmosphere and curved back out again. Was it an ET craft? The narrator sure thought so. He said that only a piloted craft could change its course, that no natural object like a "meteorite" can do that. He also said that since it "broke free of Earth's gravity", it could not have been natural either. Only man-made objects, like the Space Shuttle, can do that. This is wrong for so many reasons it makes my head ache. First off, meteors do indeed skip off the atmosphere. It works just like a rock skipping on water: if the meteor comes in at a shallow angle, it can skip along the air and change its heading, turning back into space. There is a famous case of this happening in the early 1970's, and it was seen by thousands of people. A rock the size of a bus skimmed along the atmosphere for hundreds of miles and finally skipped back out into space. Second, they called it a "meteorite", which is the wrong term: a meteorite is what a meteor is called if it hits the ground. Third, the shuttle does not "break free of Earth's gravity". It can get into orbit, but to break free would mean reaching escape velocity, leaving the Earth forever, which it cannot do. It simply does not have the fuel for that. Ironically, the narrator of the UFO show got it exactly backwards: the shuttle cannot "break free", but meteors can, and do all the time! Again, I really do have an open mind about some of this, but so much garbage is aired on TV (and the 'net is highly guilty of this as well) that it's hard to separate the real from the, well, not-so-real. I have said it before, and I'll say it again: you need to understand what's going on in the sky around you before you can claim something is a UFO. Venus, the Moon, and even the Sun can be mistaken for flying saucers if you are unfamiliar with the way they behave. I wonder how many reports of UFO's we'd hear if people paid more attention to the sky and asked about what they saw, instead of running to the nearest talk show host?
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