What does observing a galaxy with a high redshift, such as $z=6$, primarily allow astronomers to determine?

Answer

The lookback time (when the light was emitted).

The measured redshift allows scientists to determine the lookback time—how long ago the light was actually emitted—which is crucial for understanding the early universe.

What does observing a galaxy with a high redshift, such as $z=6$, primarily allow astronomers to determine?

#Videos

Why Do Galaxies have a Redshift Proportional to Distance? - YouTube

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