Will the cosmic microwave background disappear?

The cosmic microwave background (CMD) is radiation left over from the Big Bang.

25th March 2017
Will the cosmic microwave background disappear? (NASA/ESA)

Asked by: Jamie Edwards, Essex

Yes. This relic radiation left over from the Big Bang is being increasingly redshifted as the Universe expands. So its energy is being constantly diluted.

After another few trillion years, the current cosmic microwave background will have redshifted into insignificance and will no longer be detectable. In this far-flung future, the Universe will have expanded so much that even the closest galaxies will be well beyond our sight. At this time, there will be no visible evidence that the Universe is expanding or that there was ever a Big Bang! 

 


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