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Astronomy book listing Ceres as a planet?

  1. Jul 25, 2013 #1
    Does anyone know of a (relatively) cheap astronomy book which has Ceres officially labelled as a planet? I realize it may not be extremely cheap seeing that it would have to be from the 1800s, but perhaps there's one that was commonly enough in print to not be so hard to find?

    It's both useful as something to show people in helping them to understand why Pluto is no longer a planet and it would just be fun to own such a book.

    If there's a free PDF version of such a book online, that would be great to know about as well, but a physical copy would be best.

  2. jcsd
  3. Jul 25, 2013 #2
    Technically that book could be correct in the future! :biggrin:

    In many thousands of years, Ceres should clump up enough of the Asteroid Belt to form a planet.
  4. Jul 25, 2013 #3
    Jenny I would check if there is something suitable at Project Gutenberg.
  5. Jul 26, 2013 #4
    Just so no one is missinformed the above is wrong in every shape and form. The asteroid is slowly thining not clumping together.
  6. Jul 26, 2013 #5
    Oh really? :confused: Sorry.
    It was something I read a while back.
  7. Aug 2, 2013 #6
    Thanks for the Project Gutenberg, I will give that a try for sure.
  8. Aug 2, 2013 #7


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    Also, even if Ceres did manage to collect all of the mass of the asteroid belt, it still would only be <1500km across, and have less than 5% of the mass of the moon - not nearly enough to qualify as a planet.
  9. Aug 2, 2013 #8
  10. Aug 3, 2013 #9
    Ceres, Georgian, and Other Planets

    I followed the link Jenny gave and see that the book was published in 1816 in Cambridge. Among the planets it lists are Ceres, Pallas, Juno, Vesta, and Georgian. Most of these names are probably familiar as the names of asteroids, but what is "Georgian"?

    After William Herschel discovered a new planet in 1781 he had the honor of naming it. To quote Wikipedia: "Herschel decided to name the object Georgium Sidus (George's Star), or the 'Georgian Planet' in honour of his new patron, King George III...Herschel's proposed name was not popular outside of Britain, and alternatives were soon proposed." No kidding! The name finally agreed-upon "...became universal in 1850 when HM Nautical Almanac Office, the final holdout, switched from using Georgium Sidus to Uranus."

    Interestingly, another proposed name for the planet was "Neptune," which became the name of the next planet discovered.
  11. Aug 3, 2013 #10


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    If the whole asteorid belt would clump together, it would be a planet, based on the current definition of planets:
    • it would orbit the sun - obvious
    • it would be in (approximate) hydrodynamic equilibrium - that is satisfied, Ceres alone is big enough for that
    • it would have cleared its orbit of other objects - that is the assumption of the scenario
  12. Aug 3, 2013 #11


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    You're right of course, but it would be a very small planet.
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