Is it a stable/static effect no matter what, or is it a bit more stretchy/bouncy depending on how the object is behaving?

Thank you!

  • Boddhisatva@lemmy.world
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    6 months ago

    First, no object could be accelerated to that speed. Relativistic effects make that impossible. However, gravity waves move at the speed of light so there is some delay in gravitational effects. I’m not a physicist, but I’m pretty sure that if your sun-sized object shot through the solar system at 99.9999% the speed of light, and passed between the Earth and the Sun, it would take about 4 minutes for the object’s gravity to be felt by either the Earth or the Sun.

    • 58008@lemmy.worldOP
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      6 months ago

      Wow, that’s an incredible thought. So “ziiiiiiip” there goes the uberobject. 4 minutes later, all of the budgies on earth are knocked off their perches.

      Would that uberobject heat up the earth as it passes? Not sure how that would work, but it seems like a good question 🤣

      • Boddhisatva@lemmy.world
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        6 months ago

        Again, not a physicist, so here’s a bunch of words that sum up to “maybe.”

        With the object moving so fast I’m not sure we’d notice anything much. We would only be in it’s gravitational field for a very short time, but it might be long enough to change Earth’s orbit, someone with better math skills will need to field that one.

        As for heating the Earth, again that’s a maybe. Gravity is stronger the closer you are to the center of mass. So the near side of the Earth will feel the pull of the object much more strongly than the further side. That will make the Earth want to stretch towards the object as the near side falls towards the object faster than the far side. It would be very slight, think egg-shaped but not to a noticeable degree, but it could be bad enough.

        This is called a tidal effect and would generate some heat if we’re in the gravity well of the object for long enough. It would also cause fault lines to pop all over the globe. The object would shoot by very quickly though at 99.9999c so we might be spared the worst of the effects. Again, someone with better math skills could give a more accurate answer.

        FYI tidal effects are why the moons of the gas giants aren’t frozen ice balls. The constant flexing as they orbit their planet generates tremendous amounts of heat.