What astronomical scale makes the AU impractical as a primary unit of measurement?

Answer

Distances between stars outside our solar system.

For measuring distances between other stars, such as those associated with exoplanets, the AU becomes too small and units like light-years or parsecs are preferred.

What astronomical scale makes the AU impractical as a primary unit of measurement?

#Videos

What Does AU Mean In Astronomy? - Physics Frontier - YouTube

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