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Cake day: June 4th, 2023

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  • That definition means a planet has nothing to do with physical state, and everything to do with the proximity of your neighbors. We could promote the Moon to a planet by pushing it further away, or demote Earth from being a planet by slinging it a bit closer to it’s hungry uncle Jupiter. We could demote all planets by extinguishing the Sun! Then the entire system stops working and it’s all just asteroid or something.

    That arbitrarily chosen definition doesn’t describe the object, only it’s place in the malleable hierarchy. With this, the title of planet tells us nothing about the object itself, except that it’s orbit is only dominated by a star.

    Even worse, the IAU definition is extra arbitrary, as it only counts objects that orbit specifically the Sun, so the vast majority of bodies in hydrostatic equilibrium that don’t fuse hydrogen aren’t planets. They also play very lose with hydrostatic equilibrium, as Mercury isn’t in hydrostatic equilibrium, yet is explicitly classified as a planet. And “clearing it’s orbit” is also rather indistinct, with no method to determine this is given. It’s up to argument if Neptune is a planet, as many plutoids intersect it’s orbit.

    Even more worse, the barycentre of our solar system is sometimes outside of the sun! That means sometimes the Sun is co-orbiting with the rest of the solar system bodies, and therefore by this definition nothing is a planet! It’s a definition so arbitrary that it periodically stops existing!

    I’m not just saying I disagree with the IAU here, but that their definitely is objectively poor, and poorly used. I agree that Pluto, Eris, Ceres, and many others should be in a different category from Jupiter, but make some categories that make sense, please!



  • Tlaloc_Temporal@lemmy.catoScience Memes@mander.xyzTell me the truth.
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    1 month ago

    Pluto and Charon orbit each other. The barycentre (the center of mass they both orbit) is far outside of Pluto. The Earth-Moon barycentre is still inside Earth, though this could be changed by moving the Moon further out.

    Either way, Earth, the largest rocky planet, could be made into a moon by sending it to Jupiter, so I don’t think being a moon should disqualify a celestial body from being a planet.


  • There’s also plenty of classifications of plants based on form! Non-vascular plants, woody plants, herbaceous plants, algae and lichen…

    Most of our “rocky” planets are pretty wet though. Mars is drying out, but Venus is caked with volatile chemicals and Earth is downright infected. Only Mercury is really barren, partly due to it’s small size. I could easily see three categories for gravitationally rounded bodies that can’t fuse hydrogen: Dry planets (usully smaller), Wet planets (usually larger), and Gaseous planets (gas giants).



  • Oh, that chemistry is great, but I don’t think he plays the investigator part well, especially when trying to follow the clues left by Dr Lanning. Will Smith’s style is very off the cuff and anti-authority, and while that works in MIB where there’s the very strict Agent K to play off of, I don’t think he works as the sole driver of a light mystery. Sonny and Spooner’s interactions are fantastic, but they’re usually driven by Sonny giving exposition. Spooner is usually just running from things as they unfold.

    All in all, not a bad performance (there were plenty of objectively worse ones), but I don’t think it does the movie any favours. There are plenty of great things about i, Robot, but Will Smith is not one of them in my opinion.



  • The crucifix is an implement of torture and execution, upon which the titular Christian god was executed to fulfill a blood oath. Executionists, torturers, blood magicians, nailers, death cultists, the forsaken (Psalm 22)…

    Being shephered by a higher authority is also a common theme. Sheep is right there, although some actually use that directly.

    Another common theme is the second arrival of their god, starting the end of the mortal realm and the death of all mortals. Death cultists again, apocalyptics, doomsdayers…

    There’s lots of heinous things in their book, but most reject them or are unaware. You could call out lots of things there.





  • That’s cool, but please label your axes!

    Your first graph insinuates that there’s a constant spawn of prometheum asteriods before speed spawns anything. I wonder if that’s actually a baseline spawn or if promethium has a different speed multiplier to the other asteroids…

    It also insinuates that the factoriopedia uses a baseline speed of 20km/s for it’s graphs. That could be tested on the other routes as well.

    There may also be a limit on the number of asteroids allowed to exist at once. I wonder if how soon after spawning they are destroyed affects rates. This could be tested with a skinny long ship with a wide base, where asteroids are spawned at the front but not destroyed ontil they reach the wide rear.


  • Blaschko’s lines happen mostly in mosaicism, where an embryo is formed by the fusion of two embryos, gets a mutation early in development, or otherwise gets two different genotypes. It can also be caused by X-linked genes. If those genotypes produce different skin colours or react differently to skin diseases, you can see the lines directly.

    It looks like any visible form of mosaic disease may present along Blaschko’s lines.


  • There’s lot’s of issues with current physics, mostly in cosmology. String Theory was partly invented to describe the interior of a black hole. The characteristics of the Higgs field are still unknown. Gravity is still not unified with the other forces, despite appearing to couple with everything. Our current best models for the formation of the universe predict huge amounts of invisible matter, and we have no idea what that could be, from new particles to microscopic black holes formed in the first nanoseconds of the universe, to reinterpretations of relativity. Those same models also predict that out universe is dominated by strange energy inherent to space itself, which has no basis in the Standard Model at all. I wouldn’t call these perfectly fine answers.

    And even if the nature of the interior of a black hole what the only issue, the final part of physics we haven’t explained, I would say we’ve thought that before. About a century ago, the scientific community though they had mostly solved physics. The last big question was why ultraviolet light didn’t extend out to infinite energy as predicted. Then photons happened and we discovered quantum physics.