Museo Galileo
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Virtual Museum
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Fixed stars
Fixed stars

Heavenly bodies that were regarded as occupying immobile relative positions on the celestial sphere but do not appear immobile to the observer on Earth. So called to distinguish them from the planets, whose name (from the Greek planétes) means wandering. In the Aristotelian-Ptolemaic system, the heaven of the fixed stars (eighth sphere) enclosed the planetary heavens.