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Physics/Planet revolution period



It seems that Indian astrologers were aware that Saturn revolution period is around 29 years several centuries earlier. They incorrectly believed in Geocentrism. How could the ancient Indian astronomers know about the revolution period of some planets accurately. Can it be known by naked eye observations.


I can see them observing some variability in brightness, but honestly they couldn't have actually observed it revolving directly.  It's difficult to observe any details of planets, even with a decent backyard telescope.  But it's remotely conceivable that they could've observed variations in brightness and ascribed a "periodicity" to it.  The difficulty in believing that is that they'd have to observe a variability in it from night to night, so it's far more likely to be a coincidence with the lunar orbit period.


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Dr. Stephen O. Nelson


I can answer most basic physics questions, physics questions about science fiction and everyday observations of physics, etc. I'm also usually good for science fair advice (I'm the regional science fair director). I do not answer homework problems. I will occasionally point out where a homework solution went wrong, though. I'm usually good at explaining odd observations that seem counterintuitive, energy science, nuclear physics, nuclear astrophysics, and alternative theories of physics are my specialties.


I was a physics professor at the University of Texas of the Permian Basin, research in nuclear technology and nuclear astrophysics. My travelling science show saw over 20,000 students of all ages. I taught physics, nuclear chemistry, radiation safety, vacuum technology, and answer tons of questions as I tour schools encouraging students to consider careers in science. I moved on to a non-academic job with more research just recently.

Ph. D. from Duke University in physics, research in nuclear astrophysics reactions, gamma-ray astronomy technology, and advanced nuclear reactors.

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