Historically, how was the AU initially determined before 2012?

Answer

As an empirical measurement derived from observations of Earth's elliptical orbit.

The initial derivation of the AU relied on tracking the variations in the physical distance between the Earth and the Sun as the Earth followed its elliptical path, resulting in an average figure.

Historically, how was the AU initially determined before 2012?

#Videos

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

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