The New Heavens and New Earth are an event that occurs at the end of the 1000 year millennial period and are more or less a complete reboot of the universe as we know it. In remaking all of creation, God will basically "reboot" everything and return it back to the sinless perfection it once enjoyed at the Garden of Eden, or perhaps even better. Since this event is still far off, little is known about it, save only that it'll eventually happen. It's possible that more will become known about it during the Millennium, but that's only theory. We may have to wait until the actual event to learn all there is to know about this new creation, and see it with our own eyes. But suffice it to say, this will come to reality some day.
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