What powerful insight does the relationship between redshift ($z$) and distance provide astronomers?

Answer

It acts as a direct cosmic distance ladder

The greater the measured redshift, the farther away the object is located, enabling astronomers to map the three-dimensional structure of the universe across different epochs by knowing the lookback time.

What powerful insight does the relationship between redshift ($z$) and distance provide astronomers?

#Videos

What Does Redshift Tell Us About Distant Galaxies? - Physics Frontier

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