this post was submitted on 05 Oct 2024
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Showerthoughts

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A "Showerthought" is a simple term used to describe the thoughts that pop into your head while you're doing everyday things like taking a shower, driving, or just daydreaming. A showerthought should offer a unique perspective on an ordinary part of life.

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It was only in 1969 (nice) that fungi officially became its own separate kingdom.

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[–] CheeseNoodle@lemmy.world 3 points 1 month ago (1 children)

Actually planet doesn't have any hard set definition, we kind of just do it case by case because its damn near impossible to come up with a rigid definition that doesn't suddenly classify some planets as moons or some moons as planets or create weird situations in which an object can switch between the two.

[–] wanderer@lemmy.world 4 points 1 month ago (1 children)

The International Astronomical Union (IAU) defined in August 2006 that, in the Solar System, a planet is a celestial body that:

  1. is in orbit around the Sun,
  2. has sufficient mass to assume hydrostatic equilibrium (a nearly round shape), and
  3. has "cleared the neighbourhood" around its orbit.

https://en.wikipedia.org/wiki/IAU_definition_of_planet

[–] CheeseNoodle@lemmy.world 5 points 1 month ago (1 children)

And in that same article:

It has been argued that the definition is problematic because it depends on the location of the body: if a Mars-sized body were discovered in the inner Oort cloud, it would not have enough mass to clear out a neighbourhood that size and meet criterion 3. The requirement for hydrostatic equilibrium (criterion 2) is also universally treated loosely as simply a requirement for roundedness; Mercury is not actually in hydrostatic equilibrium, but is explicitly included by the IAU definition as a planet

[–] Draconic_NEO@lemmy.world 2 points 1 month ago

That's not even addressing the issue of rogue planets which were ejected from their star system. Many estimates say they outnumber the stars. Obviously when a planet is ejected it doesn't just disintegrate but by that poor definition it's no longer a ""planet"", so it's clearly a problematic definition.