[mtnman]

The TFES wiki https://wiki.tfes.org/Planets has an article about planets. It claims that while the sun orbits the hub of the Earth (I guess that means the center we see as the north pole) and that the planets in turn orbit the sun. It also says that the retrograde motion that we see in the path of the planets across the sky is because of the combined motion of the planet orbiting the sun and the sun orbiting the north pole.



It doesn't explicitly say this, but to me that seems to imply that the orbits of all the visible planets have similar orbits to the diagram on the page, putting their orbits within the distance from the north pole/hub to the sun. Is this understanding correct?

[Excelsior John]

The TFES wiki https://wiki.tfes.org/Planets has an article about planets. It claims that while the sun orbits the hub of the Earth (I guess that means the center we see as the north pole) and that the planets in turn orbit the sun. It also says that the retrograde motion that we see in the path of the planets across the sky is because of the combined motion of the planet orbiting the sun and the sun orbiting the north pole.



It doesn't explicitly say this, but to me that seems to imply that the orbits of all the visible planets have similar orbits to the diagram on the page, putting their orbits within the distance from the north pole/hub to the sun. Is this understanding correct?

Not all the planets orbits are exacley simalar to the won shown in the diagram. Yes, they all orbit around the sun wile the sun orbits abuv the Earth thus explaneing retrograde motion. However only Mercurey and Venus wuld look exacley like the diagram ,ware those planets are at won point batween the sun and the North Pole/Hub. The orbits of Mars and the owter planets are largur then the distinse batween Earth and the Sun so they are nevar batween the Earth and the Sun. So to anser your qwestion, all the planets have the same basicks as in the diagram, but no,only Mercurey and Venus are batween the Sun and the North Pole

[GiantTurtle]

But in FET the Mercury and Venus are the only two planets that orbit over and underneath the sun right?
Otherwise they could not be closer than the sun on both the inner and outer hemispheres.

[mtnman]

Not all the planets orbits are exacley simalar to the won shown in the diagram. Yes, they all orbit around the sun wile the sun orbits abuv the Earth thus explaneing retrograde motion. However only Mercurey and Venus wuld look exacley like the diagram ,ware those planets are at won point batween the sun and the North Pole/Hub. The orbits of Mars and the owter planets are largur then the distinse batween Earth and the Sun so they are nevar batween the Earth and the Sun. So to anser your qwestion, all the planets have the same basicks as in the diagram, but no,only Mercurey and Venus are batween the Sun and the North Pole

If FE explains retrograde motion using a circle within a circle for planets that orbit between the sun and the Earth, then there would have to be a different explanation for ones that orbit in a larger circle around the sun.

Do you also subscribe to the belief that the sun is 3000 miles above the Earth? If so, does that also mean that Mercury and Venus are also 3000 miles above us, somewhere between the sun and north pole (during that part of their orbit)?

[Excelsior John]

But in FET the Mercury and Venus are the only two planets that orbit over and underneath the sun right?
Otherwise they could not be closer than the sun on both the inner and outer hemispheres.

I dont think Mercurey and Venus orbit over and undurneth the Sun (as in north-sowth, if thats what your saying). When I sayed they were closur I ment they were closur to the North Pole in an east-west direction, not nesasareley undurneth the Sun

Not all the planets orbits are exacley simalar to the won shown in the diagram. Yes, they all orbit around the sun wile the sun orbits abuv the Earth thus explaneing retrograde motion. However only Mercurey and Venus wuld look exacley like the diagram ,ware those planets are at won point batween the sun and the North Pole/Hub. The orbits of Mars and the owter planets are largur then the distinse batween Earth and the Sun so they are nevar batween the Earth and the Sun. So to anser your qwestion, all the planets have the same basicks as in the diagram, but no,only Mercurey and Venus are batween the Sun and the North Pole

If FE explains retrograde motion using a circle within a circle for planets that orbit between the sun and the Earth, then there would have to be a different explanation for ones that orbit in a larger circle around the sun.

Oh contrare. The same explanation extends to the owter planets, as the suns motion around Earth also creates retrograde motion for Mars, Jupitur, etc. The grete astrominur Tycho Brahe expland retro motion using this argumint as seen from his geoheliocentric "Tychonian sistum" balow:

This concep is furthur expland in this link:
https://physics.stackexchange.com/questions/38305/how-is-retrograde-motion-explained-in-tychos-model

Do you also subscribe to the belief that the sun is 3000 miles above the Earth? If so, does that also mean that Mercury and Venus are also 3000 miles above us, somewhere between the sun and north pole (during that part of their orbit)?

No I dont, I beleive the Sun to be aproximitley 93 milion miles away and 865,000 miles in diamiter. However, I wuld asume that those who beleive in the close sun thoery also beleive that Mercurey and Venus are abowt the same distinse, but I think somewon who subscribes to that thoery wuld be beter sewtid to anser your qwestion

[mtnman]

I would love to see an animation of this belief system since it makes no sense to me.

If the sun is orbiting the Earth, and Jupiter is orbiting the sun, as depicted here, then Jupiter's position against the background stars would change drastically over the course of a single night from sundown to sunrise. This is not the case.

[GiantTurtle]

I dont think Mercurey and Venus orbit over and undurneth the Sun (as in north-sowth, if thats what your saying). When I sayed they were closur I ment they were closur to the North Pole in an east-west direction, not nesasareley undurneth the Sun

If that was true then they could only be closer to one hemisphere at a time. They are observed to be closer than the sun to both North and South hemispheres at the same time. The only way it can be is if they are lower down than the sun is.

[3DGeek]

The problem with all of this is that it's inherently a geocentric system - and not heliocentric.

Back when geocentricism was all the rage - they ended up with more and more complex explanations for the orbits of planets that became SO insanely complex that it was eventually abandoned in favor of the much simpler heliocentric system.

It was abandoned long before some of the outer planets were discovered (good luck explaining the orbit of Pluto that way!) - and before the moons of other planets were discovered - which makes geocentricism much less credible.

[GiantTurtle]

Back when geocentricism was all the rage - they ended up with more and more complex explanations for the orbits of planets that became SO insanely complex that it was eventually abandoned in favor of the much simpler heliocentric system.

Do you know where I can find these equations, I could do an animation for the wiki.

[garygreen]

Back when geocentricism was all the rage - they ended up with more and more complex explanations for the orbits of planets that became SO insanely complex that it was eventually abandoned in favor of the much simpler heliocentric system.

Do you know where I can find these equations, I could do an animation for the wiki.

the equation of motion in this case would be a series of plane waves (think sine wave).  each wave gets some scaling factor, and the sum of all the waves is a single path that describes whatever planet you're talking about.

something like this: 

interesting historical side-note: epicycles weren't really abandoned because of complexity.  modern tables of planetary positions, for example, are computed from equations of motion that may contain thousands of terms.  it has more to do with the arbitrariness of the epicycle model.  any path can be described as a sum of plane waves, so epicycles don't end up telling you anything physical about why a planet moves as it does.