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23: The Planets

  • Page ID
    4751
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    Most stars we observe form fixed constellations in the sky, undergoing daily motion (e.g. rising and setting) but maintaining fixed positions relative to each other -- like the stars of Orion or the Big Dipper. However, the ancients noted that 5 stars constantly moved -- all following close to the paths of the Sun and Moon across the heavens, i.e., close to the ecliptic. The Greeks called them planets -- Greek for wanderers -- a name still used.


    23: The Planets is shared under a CK-12 license and was authored, remixed, and/or curated by CK-12 Foundation via source content that was edited to conform to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.

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