» Analemma was also a book by Ptolemy. In astronomy, an analemma (IPA: /ˌænəˈlɛmə/, Latin for the pedestal of a sundial) is a curve representing the angular offset of a celestial body (usually the Sun) from its mean position on the celestial sphere as viewed from another celestial body (usually the Earth). For instance, knowing that Earth's average solar day is almost exactly 24 hours, an analemma can be traced by plotting the position of the Sun as vie… (
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