The mathematics of stargazing, from René Descartes' 'Discourse on Meteorology', 1637
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Constellation Libra,15th c edition of Abd ar-Rahman as-Sufi, The Book of Fixed Stars, originally compiled in 964 CE
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A personification of the Four Winds from a medieval illuminated manuscript
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BTW-type locale in NASA site and receive alerts when the ISS can be viewed. It's cool spotthestation.nasa.gov
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Isn't this the geometry of a rainbow? Looks like internal reflections in a raindrop....
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It is, I think
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