• gandalf_der_12te
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    6 hours ago

    do those orbits get larger over time?

    Yes, I think they do.

    I think that expansion doesn’t increase distance, but velocity between objects (or so was my interpretation back when I looked at the formulas). That means that moving objects speed up over time. As such, orbital velocities increase, too, and that lifts their orbit - similar to when a rocket on a closed orbit propulses forward.

    But I might be wrong; I feel 70% certain about this one.

    • Kichae@lemmy.ca
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      4 hours ago

      But I might be wrong; I feel 70% certain about this one.

      You should downgrade your certainty. By a lot.

      The expansion is an expansion of space, and therefore explicitly increases the distance between galaxies. It does not, and cannot increase the speed at whoicj those galaxies travel through that space.

      Right now, there are galaxies moving away from us at rates higher than the speed of light, a thing which is physically not possible if the expansion is due to an acceleration of the galaxies themselves.

      You’ve misunderstood things completely backwards.