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If 'geocentrism' means that you can regard the Earth as stationary and describe the motion of Sun and planets accordingly, then geocentrism isn't wrong.

But if 'geocentrism' means that The Sun and planets have simple (for example circular) orbits about the Earth, then it is wrong. Almost 2000 years Ago, Ptolemy knew that a geocentric solar system based on circles needed the planets to move in circles nested on circles nested on circles in order for theory to match observation. [This is analogous to a Fourier analysis of a complicated shape of orbit.]

A heliocentric system based on circles rather than ellipses still needs these 'epicycles', but smaller ones and fewer of them. I'd add that I think it's perfectly reasonable to teach children that the Earth and other planets "go round the Sun". There's no reason, though, to say to them that the Sun, any more than the Earth, is stationary.

If 'geocentrism' means that you can regard the Earth as stationary and describe the motion of Sun and planets accordingly, then geocentrism isn't wrong.

But if 'geocentrism' means that The Sun and planets have simple (for example circular) orbits about the Earth, then it is wrong. Almost 2000 years Ago, Ptolemy knew that a geocentric solar system based on circles needed the planets to move in circles nested on circles nested on circles in order for theory to match observation – which for some planets even involves their stopping and going backwards for a while. [The nested circle treatment is analogous to a Fourier analysis of a complicated shape of orbit.]

A heliocentric system based on circles rather than ellipses still needs these 'epicycles', but smaller ones and fewer of them. I'd add that I think it's perfectly reasonable to teach children that the Earth and other planets "go round the Sun". There's no reason, though, to say to them that the Sun, any more than the Earth, is stationary.

If 'geocentrism' means that you can regard the Earth as stationary and describe the motion of Sun and planets accordingly, then geocentrism isn't wrong.

But if 'geocentrism' means that The Sun and planets have simple (for example circular) orbits about the Earth, then it is wrong. Almost 2000 years Ago, Ptolemy knew that a geocentric solar system based on circles needed the planets to move in circles nested on circles nested on circles in order for theory to match observation. [This is analogous to a Fourier analysis of a complicated shape of orbit.]

[A heliocentric system based on circles rather than ellipses still needs these 'epicycles', but smaller ones and fewer of them.]

If 'geocentrism' means that you can regard the Earth as stationary and describe the motion of Sun and planets accordingly, then geocentrism isn't wrong.

But if 'geocentrism' means that The Sun and planets have simple (for example circular) orbits about the Earth, then it is wrong. Almost 2000 years Ago, Ptolemy knew that a geocentric solar system based on circles needed the planets to move in circles nested on circles nested on circles in order for theory to match observation. [This is analogous to a Fourier analysis of a complicated shape of orbit.]

A heliocentric system based on circles rather than ellipses still needs these 'epicycles', but smaller ones and fewer of them. I'd add that I think it's perfectly reasonable to teach children that the Earth and other planets "go round the Sun". There's no reason, though, to say to them that the Sun, any more than the Earth, is stationary.

If 'geocentrism' means that you can regard the Earth as stationary and describe the motion of Sun and planets accordingly, then geocentrism isn't wrong.

But if 'geocentrism' means that The Sun and planets have simple (for example circular) orbits about the Earth, then it is wrong. Almost 200 years Ago, Ptolemy knew that a geocentric solar system based on circles needed the planets to move in circles nested on circles nested on circles in order for theory to match observation. [This is analogous to a Fourier analysis of a complicated shape of orbit.]

[A heliocentric system based on circles rather than ellipses still needs these 'epicycles', but smaller ones and fewer of them.]

If 'geocentrism' means that you can regard the Earth as stationary and describe the motion of Sun and planets accordingly, then geocentrism isn't wrong.

But if 'geocentrism' means that The Sun and planets have simple (for example circular) orbits about the Earth, then it is wrong. Almost 2000 years Ago, Ptolemy knew that a geocentric solar system based on circles needed the planets to move in circles nested on circles nested on circles in order for theory to match observation. [This is analogous to a Fourier analysis of a complicated shape of orbit.]

[A heliocentric system based on circles rather than ellipses still needs these 'epicycles', but smaller ones and fewer of them.]