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Old 10-November-2007, 12:18 AM
neilzero neilzero is offline
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Our galaxy and some other galaxies are spirals. Our galaxy takes about 1/4 billion years, to make one turn. If the 20 or so galaxies in our local group are a spiral (probably not), one turn would take perhaps 10 billion years. A group of 100 galaxies would likely take much longer than the age of the Universe to complete even a small fraction of a turn. For the 200 billion galaxies we can see (if spiral) would turn almost none in 13.7 billion years = the age of the Universe. So spiral or not is pretty much irrellevent. We likely will never know about the portion of the Universe which is receeding faster than light speed, but there likely is a significant portion of the Universe that is receeding faster than light speed.
Going toward smaller, our solar system and the moons of the gas giant planets, do not appear to be spiral, molecules apparently are only occasionaly spiral. we don't think atoms are spiral, so we should not assume spirals are common except for some of the galaxies. There are a few experts who think the spiral structure of galaxies is an optical illusion. Neil
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