This was a really well written article describing what we know about Neptune.

  • Old_Dude@sh.itjust.works
    link
    fedilink
    arrow-up
    3
    ·
    1 year ago

    I assumed gravity would be more than 14% of the gravity on Earth but just found out the size of Neptune is a lot smaller than I had imagined. It’s only 4 times the diameter of Earth, while Jupiter is 1,300 times the diameter of Earth. I didn’t realize the size difference between the two were so far off.

    • Freeman@lemmy.pubOP
      link
      fedilink
      arrow-up
      2
      ·
      1 year ago

      To be fair jupiter is 99% of the mass in the solar system (that isnt the sun).

      The sun is 99.8% of the mass of the entire system

      Of the rest of the .15-.2% of the mass left, Jupiter is like 2.5x bigger than the rest of the stuff combined.

      Jupiter is really big. So if the sun.

    • Freeman@lemmy.pubOP
      link
      fedilink
      arrow-up
      5
      ·
      1 year ago

      The reality is we dont really know. The “surface” in this article is where the pressure is largely 1 atm. And at that pressure its mostly liquid (albeit hot)

    • shadowspirit@lemmy.world
      link
      fedilink
      arrow-up
      3
      ·
      edit-2
      1 year ago

      That’s a good question that hopefully someone more learned will be able to respond to but you know most of the Earth’s surface is water so I suppose Neptune has a surface. I don’t know what the technical definition is but I’m assuming it’s where particulate / molecules in the atmosphere change states due to temperature and pressure. A bit like how we have H2O in the form of gas as water vapor in the atmosphere and at the surface a liquid as water. The closer you are to the center of the planet the higher the pressure and the temperature.

      • octoperson@sh.itjust.works
        link
        fedilink
        arrow-up
        3
        ·
        1 year ago

        If the pressure is high enough, you can get a smooth transition between gas and liquid without any sort of boundary that you could identify as a surface. That’s thought to be what happens on Jupiter, don’t know about Neptune