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The accelerating expansion of space means that the space between us and far away galaxies expands faster than light can travel through space. There is a horizon of possible observation beyond which galaxies disappear from us.

At what rate do galaxies, or some other measurement of mass/energy, disappear beyond that horizon at present rate? Will future telescopes actually see galaxies red shift themselves into oblivion? I imagine there being issues about the definitions of "when" and "where" in this context. Answers should try to address how they deal with that.

Since the radius of the observable universe expands at the speed of light, my intuition tells me that there should've been a point in time when the expansion of space balanced the arrival of light of more distant parts of space. if so, when did that happen?

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