• chonglibloodsport@lemmy.world
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    2 days ago

    Gravity wells don’t have breakpoints like that though. They extend out to infinity, decreasing with the reciprocal square of the distance (Inverse-square law).

    What you may be thinking of is the event horizon, but the way that works isn’t nearly as magical as people might think. As your orbit spirals in closer to the black hole (which takes an extremely long time from a stable orbit) your escape velocity gradually and smoothly increases. The event horizon is the point at which your escape velocity reaches the speed of light. What this means in practice is that you disappear from view, as the light reflecting off you can no longer escape.

    The really weird part though is the gravitational time dilation effects near a black hole. To an outside observer, your approach to the event horizon (during spiral in) slows down more and more. That observer never sees you cross the event horizon because time dilation extends your descent time out to infinity. So you’ll end up appearing frozen in time, never reaching the event horizon.

    • SLVRDRGN@lemmy.world
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      1 day ago

      Haha yes, well explained. I’m familiar with this info (actually just finished reading Black Holes & Time Warps: Einstein’s Outrageous Legacy, by Kip Thorn which I highly recommend if you’re into this).

      I meant event horizon, in this instance, but yes this comic isn’t meant to be accurate anyway (last pane). But to your original point - wouldn’t the black hole be a vacuum cleaner for all things within its event horizon?

    • Naz@sh.itjust.works
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      2 days ago

      Hell yeah, this is the best explanation of black hole + orbital mechanics and time properties I’ve seen published on the Internet

      Thank you for internalizing and actually understanding the phenomenon

      +1 Lemmy Coin 🪙