Why is the parsec often preferred over the light-year in professional observational astronomy?

Answer

It is directly linked to the geometric parallax measurement method via trigonometry.

Because the parsec derives directly from the observed angular shift (parallax) using triangulation, it offers a more immediate mathematical output for observational data than the time-based light-year.

Why is the parsec often preferred over the light-year in professional observational astronomy?

#Videos

What is Parsec ? How 1 parsec is measured? - YouTube

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