https://xkcd.com/2908

Alt text:

Astronomers are a little unsure of the applicability of this index, but NASA’s Planetary Protection Officer is all in favor.

  • kernelle@0d.gs
    link
    fedilink
    English
    arrow-up
    90
    arrow-down
    1
    ·
    edit-2
    9 months ago

    One of my all-time favourite facts is that solar eclipses are actually a very rare thing to happen in space. There is no reason why but our moon just happens to be the right size/distance to have this happen.

    I’ve never seen one in person, but the next one is on the 8th of April crossing Mexico and the US. If you have the chance and are able, go check it out, if only to gloat on an internet stranger longing for his first total eclipse.

    • nyctre@lemmy.world
      link
      fedilink
      English
      arrow-up
      17
      ·
      9 months ago

      Saw one when I was 9 like 20 years ago. Still one of the coolest things I’ve ever seen. Definitely worth a trip if you can.

      • carbonari_sandwich@lemm.ee
        link
        fedilink
        English
        arrow-up
        13
        ·
        9 months ago

        And keep in mind that the difference between a total eclipse and a partial eclipse is massive. It’s worth it to find a spot that is in the line of totality.

          • TheRealLinga@sh.itjust.works
            link
            fedilink
            English
            arrow-up
            5
            ·
            9 months ago

            I got to see one about 7 years ago. Made a whole vacation of it, and was not disappointed. In the darkness, all the birds stopped singing. And to top it off, at the motel I stayed there was a cleaning lady yelling at me to get back into my room because this was a sign from her god saying this was the end of days.

      • Skua@kbin.earth
        link
        fedilink
        arrow-up
        7
        ·
        9 months ago

        One passed over my area while I was at university, and the professor whose class we were meant to be in just said the day beforehand that he wasn’t even going to bother scheduling anything for the first hour because he didn’t expect anyone to be in. There’s a famous hill-top cemetery in the city, and sure enough I saw basically all of my classmates there too

        • Spzi@lemm.ee
          link
          fedilink
          English
          arrow-up
          3
          ·
          9 months ago

          There’s a famous hill-top cemetery in the city, and sure enough I saw basically all of my classmates there too

          That was an unexpected dark turn. Glad you live to tell their story!

          • Skua@kbin.earth
            link
            fedilink
            arrow-up
            3
            ·
            9 months ago

            Strange things happen under an eclipse, and strangest of them all was a class full of undead attending lectures

    • topinambour_rex@lemmy.world
      link
      fedilink
      English
      arrow-up
      10
      ·
      9 months ago

      As Moon is slowly moving away, at some point in the future there will be no more full eclipse. And there is 2 full eclipse by year !

      • MonkderZweite@feddit.ch
        link
        fedilink
        English
        arrow-up
        3
        arrow-down
        8
        ·
        9 months ago

        Nah, it’s just a moving away, then moving closer again thing over millions of years. Balance between gravity and centrifugal force.

        • teft@lemmy.world
          link
          fedilink
          English
          arrow-up
          9
          ·
          9 months ago

          This is incorrect. The moon is moving away from the earth and will stop. At some point in the future the tidal forces will balance out and the earth-luna system will be tidally locked. From that point on they will remain locked in orbit neither moving away or towards one another unless some other large gravitational force perturbs them (e.g. an extra solar planet wandering through the solar system and passing by earth-luna).

    • Tylix@lemmy.world
      link
      fedilink
      English
      arrow-up
      3
      arrow-down
      1
      ·
      9 months ago

      I’m gonna be dead center for it here in Ohio, so excited. Got my welding helmet ready to watch it and the day off.

      • kernelle@0d.gs
        link
        fedilink
        English
        arrow-up
        1
        ·
        9 months ago

        Fuck yes, enjoy bud. I’ve read people not using high enough rated welding goggles and getting eye damage though. I’d stay on the safe side and get appropriate solar eclipse glasses. You’ll be looking directly at the sun for several minutes after all.

        • Tylix@lemmy.world
          link
          fedilink
          English
          arrow-up
          3
          arrow-down
          1
          ·
          9 months ago

          I have shade 14 capable welding helmets, I’m good. I did have to look that up to be sure though. You are right apparently to be worried.

  • 342345@feddit.de
    link
    fedilink
    English
    arrow-up
    29
    ·
    edit-2
    9 months ago

    Putting on our moon armour could solve a lot of problems. It’s not my most favourite solution though.

    PS: Gonggong?!
    Edit: dwarf planet. Discovered in 2007 and named after a god in the chinese mythology:

    Gonggong was ashamed that he lost the fight with Zhurong, the Chinese god of fire, to claim the throne of Heaven. In a fit of rage, he smashed his head against Buzhou Mountain, one of eight pillars holding up the sky, greatly damaging it and causing the sky to tilt towards the northwest and the Earth to shift to the southeast, which caused great floods and suffering.

    🤷‍♀️

    • feedum_sneedson@lemmy.world
      link
      fedilink
      English
      arrow-up
      3
      ·
      edit-2
      9 months ago

      Ah, it is Chinese, interesting. I’m guessing it’s not the gonggong in 公共汽车, because that’s a bus.

      What, it almost literally is. It’s 共工, like “work together”… but not like, go to work together (on the bus).

      • 342345@feddit.de
        link
        fedilink
        English
        arrow-up
        4
        ·
        edit-2
        9 months ago

        umm.

        These characters have multiple entirely different meanings. How does one find out what the supposed meaning is? Or is it up to the reader to decide?

        • feedum_sneedson@lemmy.world
          link
          fedilink
          English
          arrow-up
          6
          ·
          edit-2
          9 months ago

          Context, apparently the word “set” has 430 meanings in the Oxford dictionary. So there’s a lot of ambiguity. It’s very confusing but I think we give as good as we get in that regard.

  • nymwit@lemm.ee
    link
    fedilink
    English
    arrow-up
    25
    ·
    9 months ago

    Not bad, Jupiter. Considering you have 120x the surface area of earth, that’s a lot of moons.

  • teft@lemmy.world
    link
    fedilink
    English
    arrow-up
    22
    ·
    9 months ago

    See Marco Inaros was just trying to give those inners some extra planet armor.

  • mcmoor@bookwormstory.social
    link
    fedilink
    English
    arrow-up
    14
    ·
    9 months ago

    Is our moon really that big? I thought Charon-Pluto is kinda a special cases that they look like twin planets instead

    • bdonvr@thelemmy.club
      link
      fedilink
      English
      arrow-up
      34
      ·
      edit-2
      9 months ago

      It’s the largest relative moon (fifth largest in absolute terms) of any planet (sorry Pluto) and is more than a quarter as large as the earth itself. It’s also relatively further from the planet than most moons in the solar system.

      Fun fact, you can actually fit every single other planet at the same time in the space between the earth and the moon, with a bit to spare.

      • Bob Robertson IX @discuss.tchncs.de
        link
        fedilink
        English
        arrow-up
        33
        ·
        9 months ago

        Fun fact, you can actually fit every single other planet at the same time in the space between the earth and the moon, with a bit to spare.

        Though, not for very long. Gravity hates when you try things like this.

    • topherclay@lemmy.world
      link
      fedilink
      English
      arrow-up
      15
      ·
      9 months ago

      I think part of it is that Mt Everest is a lot smaller than you’d think when you’re looking at this scale. The moon is only 2% of the Earths volume so when you spread it over the Earths surface it’s really like a thin thin film to cover the whole surface. But the truth is that all of human experience is an even thinner film smeared across the surface.

          • Gloomy@mander.xyz
            link
            fedilink
            English
            arrow-up
            3
            ·
            edit-2
            9 months ago

            Yeah, but from surface to space it’s ruthly 100 km, so 43 km is quite the cover. Then again, I get what you are saying. I gues it’s a matter of perspective.

          • mcmoor@bookwormstory.social
            link
            fedilink
            English
            arrow-up
            1
            ·
            9 months ago

            Ah I see. Although the comic spreads the moon “relatively”, it presents it absolutely. Although interesting in by itself it does feels it’s missing something.

  • neptune@dmv.social
    link
    fedilink
    English
    arrow-up
    9
    ·
    9 months ago

    I mean this does have a practical application, I think. The relative masses of moons to planets does imply the moons ability to sweep junk out of the way before it hits the planet.

    • teft@lemmy.world
      link
      fedilink
      English
      arrow-up
      3
      ·
      edit-2
      9 months ago

      This is not based on mass but on volume. For example the moon is only 1% of the earth’s mass yet considerably less dense therefore it makes a thicker layer.

      • neptune@dmv.social
        link
        fedilink
        English
        arrow-up
        1
        ·
        9 months ago

        *imply

        Sure. By even the density/mechanical properites of armor will affect its usefulness. Beyond simple thickness.

    • teft@lemmy.world
      link
      fedilink
      English
      arrow-up
      6
      ·
      9 months ago

      Pluto-charon shouldn’t count since it is more akin to a binary planetary system than a planet-moon system. Charon and Pluto are so close in size that the system has a barycenter outside of Pluto. This means instead of Charon orbiting a point inside Pluto, Charon and Pluto orbit a point about 800 km above Pluto’s surface.