If a perfect instrument were available, what observation would ultimately expose the failure of the Earth-centered premise?

Answer

The prediction of no stellar parallax.

The lack of stellar parallax was used as evidence for the geocentric model because pre-telescopic instruments couldn't detect it; a perfect instrument should reveal parallax if Earth orbits the Sun.

If a perfect instrument were available, what observation would ultimately expose the failure of the Earth-centered premise?

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Believe it, Geocentric Model is TRUE - YouTube

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