• KillingTimeItself@lemmy.dbzer0.com
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      3 months ago

      as a non astrophysicist, or just a non astronomer in general. it weirds me out every time i remember that there is literally a part of the universe that apparently exists, of which we will never be able to see, because the light from that part of the universe, quite literally hasn’t reached us yet.

      The observable universe is inconceivably massive. But it just keeps going.

      And to think it’s not an improbable concept for humanity to recreate the physics behind a big bang in a controlled setting, somewhere down the line from here, is certainly an interesting thought.

      • psud@aussie.zone
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        3 months ago

        the light hasn’t reached is yet

        The light will never reach us, space is expanding faster than light between here and there

        • KillingTimeItself@lemmy.dbzer0.com
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          3 months ago

          perhaps some day we will figure out how to travel faster to light, and the metaphorical light will be capable of reaching us. Though thats also another really bizarre fact.

    • shneancy@lemmy.world
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      3 months ago

      :0 how can you be inside a star and not know it? I thought they all had a surface like our Sun

      second question, would you even feel the spaghettification? Would the signals from nerves be able to travell up to the brain?

    • unknown@sh.itjust.works
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      3 months ago

      Hi Astrophysics,

      I always wondered why they draw black holes like they do in that the accretion looks like it’s drawn in two planes. I would have thought it would have looked a bit more like a saturns rings? Or is it exactly like saturns rings but we see the whole ring bent round the top because a black hole bends the light around so we can see it? Or is it something else entirely that they are trying to depict here?

    • Captain Aggravated@sh.itjust.works
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      3 months ago

      Documentary watcher here. Isn’t the “photosphere” of the star defined by the visible surface? It is my understanding you could be “hundreds of millions of kilometers inside” the corona and not know it, but inside the photosphere?

        • xenoclast@lemmy.world
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          3 months ago

          Meaning a little less than half of that radius is way way way less than 20 million times less dense. That’s wild.

          I think about that when looking at luminous gas clouds that are millions of lys across. We can only “see” it because all the photons coming from that region of space is concentrated in a tiny visible area.

    • UnderpantsWeevil@lemmy.world
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      3 months ago

      I was under the impression that the time it would take you to get spaghettified would render the fear of such an experience irrelevant, as you’d be long dead of natural causes before then.

    • radicalautonomy@lemmy.world
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      3 months ago

      they will inevitably fall towards the centre and get spaghettified at some point

      Not before they witnessed the birth and death of thousands of civilizations! (I know they wouldn’t actually be able to witness them, not having the right equipment and being dead in due order, it’s just neat to think about relativity in that context. 😊)

    • SanndyTheManndy@lemmy.world
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      3 months ago

      What really are gravitational waves? Are they like electromagnetic waves? Do they cause orbital decay? I have so many questions.

        • psud@aussie.zone
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          3 months ago

          Surely they’re more like ocean waves; EM waves are electric and magnetic fields pulling each other up by their boot straps. Gravity waves are distortions in spacetime

      • CheeseNoodle@lemmy.world
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        3 months ago

        Gravitational waves do cause orbital decay as the energy required to create them comes from the objects own momentumn.

      • SpacetimeMachine@lemmy.world
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        3 months ago

        I highly suggest you look up PBS spacetime on YouTube. They have an incredible amount of very informative videos on black holes and gravitational waves. As well as pretty much any other astrophysics topic you can think of (and many you can’t!)

    • Evil_Shrubbery@lemm.ee
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      3 months ago

      Yes, and you are very correct.

      It’s not really possible with our minds.
      Much like with numbers, anything beyond small numbers/points our minds just turn into representative idea (a meme) which we tend to perceive on a logarithmic scale (like how people tend to think a thousand, a million, and a billion are apart by about the same-ih or only a bit differently). Thats even how our biosensory bits work, along with how we interpret/perceive information from them.

      It’s great for achieving practical stuff, but it’s not real.

      • tiramichu@lemm.ee
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        3 months ago

        The problem is the layout.

        It needs horizontal dividing lines to show that the bodies are presented in pairs at the same scale.

        When you first look at it, it seems like all six are in one picture at the same scale, then you start noticing things appearing twice, and think “hang on that’s not right” and work it out, but just two lines would have solved it immediately.

        Design, people! Design!

          • tiramichu@lemm.ee
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            3 months ago

            For you, maybe it was.

            The point of good presentation and design cues is that they can make information instantly clear to almost everyone, no matter if their brain is the size of TON 618, or not.

        • DigitalNirvana@lemm.ee
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          3 months ago

          You are, of course, quite correct. And for me today, it was the meme I needed. Dealing with the US medical system, requires perspective.

  • Ð Greıt Þu̇mpkin@lemm.ee
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    3 months ago

    Every time I see these ultramassive black holes all I see is the megastructure uber planet you can build around them, or if organic life has gone out of fashion at that point, the megastructure uber computer.

        • TheTetrapod@lemmy.world
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          3 months ago

          Great reference. The Bobs haven’t really achieved anything on this scale yet, though. The closest is the Skippies’ Matryoshka Brain, but IIRC they’re using a system of satellites around a brown dwarf star, which would be somewhat comparable in size to Jupiter. The Others’ Dyson Sphere project is closer, but I don’t think we really got a sense for how far along they were, and it looks like their home star is only a bit larger than Sol.

          Sorry if that came across as nitpicky, I was just excited to see a Bobiverse reference in the wild.

          Edit: Got the Others’ star mixed up in my head, it looks like it’s either a red dwarf or completely fictional.

    • marcos@lemmy.world
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      3 months ago

      Hard to find enough material to encircle that one.

      Maybe that’s why those “dark matter only” galaxies exist.

      • Ð Greıt Þu̇mpkin@lemm.ee
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        3 months ago

        It would take multiple galaxies of matter to pull the material together, but if you’re planning on building a megastructure of this scale that’s probably not any trouble for you

    • xenoclast@lemmy.world
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      3 months ago

      They do, but space is very big, and gravity is relatively weak in comparison.

      The strength of gravity drops off exponentially with distance. For a star to consume another star they need to be really close.

      This is made even more difficult when you consider they’re all moving through empty space really really fast.

    • psud@aussie.zone
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      3 months ago

      Look up “the great attractor”.

      The “big crunch” is the (probably incorrect) hypothesis that there’s enough mass to pull the universe into a single black hole - where everything is eaten by black holes, even all the black holes (nothing to do with the great attractor). The big bang in reverse

      • shneancy@lemmy.world
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        3 months ago

        there isn’t one! So feel free to make it up, you probably won’t find it, or won’t know when you’ve found it, but the mere act of looking will point you in the right direction - going out and enjoying the absurdly rare phenomenon of being alive. You and I are a cosmic anomaly, friend, isn’t that cool?

        for a more comprehensive guide on what do when you realise life is meaningless: refer to existentialism and absurdism

        • Lemminary@lemmy.world
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          3 months ago

          Aww, I appreciate the intent but it’s a joke. Thanks for looking out for your fellow humans, though. Good human.

  • KillingTimeItself@lemmy.dbzer0.com
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    3 months ago

    ok so, this post reminds me, a while ago i archived all of the older Vsauce content, and i binged through the vast majority of it, and i can swear there was a video from him about the scale of the universe, or the scale of things in the universe, but i can’t for the life of me find it.

    Either it’s hiding somewhere, or i’m making some shit up and it isn’t real lol.

    • shneancy@lemmy.world
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      3 months ago

      it’s quite possibly somewhere in there. The blessing and the curse of Vsauce videos is that you never know what’s going to be inside of it

        • shneancy@lemmy.world
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          3 months ago

          you got me to rewatch a couple of my favourites and there’s a bit about the scale of the singal we send out to space in Messages For the Future. Maybe it was that?

          • KillingTimeItself@lemmy.dbzer0.com
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            3 months ago

            could be, but i remember a video covering the scales of stars either as a focus, or as a reference, including a segment where the earths sun is quite literally too small to see. But i might be making that last part up.

      • KillingTimeItself@lemmy.dbzer0.com
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        3 months ago

        that’s possible, but vasuce has a very specific video style, i guess i should probably go watch a couple veritasium videos to be sure lol.

        The obvious answer is that it’s actually something related to “the scale of the universe” which is another really cool project, but i don’t think it’s that one either.