This hypothesized ninth planet (not you, sorry Pluto) might explain the unusual commonalities of extreme trans-Neptunian objects (ETNOs) 100s of AU from the sun. These ETNOs (such as dwarf planets and sednoids) have remarkably aligned orbits, suggest the existence of an undiscovered celestial body, dubbed Planet Nine, influencing them gravitationally.

    • Zachariah@lemmy.world
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      2 days ago

      Even if it’s a dwarf planet, it’s still a planet. It’s right there in the name: dwarf planet.

      This article should be about “Planet 18” since Wikipedia recognizes 17 planets already.

    • 👍Maximum Derek👍@discuss.tchncs.de
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      2 days ago

      I prefer to think of Pluto as the king of the dwarf planets and namesake of the Plutoids, rather than as a weird lesser planet not appreciably bigger than its moon.

      • volvoxvsmarla @lemm.ee
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        2 days ago

        I see Pluto and Charon as Irish twins. Or at least 2 under 2. I somehow always imagine two siblings spinning around each other. Maybe Pluto is showing a 🫶 to his little sister.

    • WoodScientist
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      2 days ago

      It can’t be the ninth planet. It literally can’t. It’s either not a planet, or its the tenth planet.

        • WoodScientist
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          2 days ago

          Exactly! Fair enough if you want to define a planet as “anything big enough to be rounded by self-gravity, but too small to undergo fusion in its core.” But there is no definition of a planet, (or at least one without an arbitrary rule like "planets have to be X km in diameter,) that allows Pluto to be a planet without Ceres also being a planet.

    • Uli@sopuli.xyz
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      2 days ago

      Yeah, I have a lot of outdated books too.

      Edit: I guess people don’t enjoy book puns?