Re:How Can a Star Be Older Than the Universe?
by mywacaday on Thursday October 17, 2019 @08:29AM
(#21281277)
As light is travelling within the expanding universe does the wavelength of distant light change over long time periods or does it appear the same because our observations are expanding too(my head hurts)>
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Re:How Can a Star Be Older Than the Universe?
by jfengel on Thursday October 17, 2019 @11:37AM
(#21283179)
Yes, the wavelength gets longer. That is, in fact, how we measure the distance: for a known frequency (say, the electrons jumping up and down in a hydrogen atom), we observe that this color is "redder" the further away an object is. The number "z" mentioned above is called the redshift because of that, and it's how we know the distances of the furthest objects.