As we are empericists, the only acceptable empirical answer to this query is that the motions are visible to us, but the mechanisms are unknown.
I'm sorry - but that's simply not true. You propose "mechanisms" for all sorts of observations - your Wiki is full of them.
For example - you observe that the sun sets - and you go one step further and say that the reason is "perspective" - so right there, you used your
observation of the setting sun to come up with a "special" kind of perspective as a
mechanism.
I asked why (if this is perspective) the sun doesn't get much smaller at the horizon because it's further away...and you tell me that the light of the sun is too bright and the laws of perspective don't apply...so again, you came up with a new mechanism (perspective works differently for bright light) to explain your observation.
If you truly did what you just claimed - then you'd have to say "
I observe that the sun sets - but I'm an empiricist - so I'm not in the business of explaining why it does that."...just as you observe the motions of the heavenly bodies but claim not to be in the business of explaining why they move as they do.
What you're doing (consciously or not) is filling in mechanisms when you think you can do so convincingly - and conveniently deciding that it's not your method to propose mechanisms when the going gets tough.
This is what gets FET into trouble - by failing to meticulously search for underlying mechanisms for everything you see, you get into contradictions - but you don't go the extra mile to fix that.
When conventional science finds a new observation that doesn't "fit" - everyone gets very excited and immediately goes on an aggressive search for the error in our "mechanisms". The anomalous behavior of the "EmDrive" rocket motor is one such example...it doesn't "fit" with our mainstream scientific thinking - and LOT of people are going to a LOT of trouble to figure out why it doesn't.
But FE theorists don't do that. When something doesn't fit it's either swept under the rug - or a new special exception is made.
For example - if the sun's apparent size at sunset does not fit what your perspective explanation for it's position predicts (mechanism #1) - then you simply add mechanism #2 (bright light is less affected by perspective) to explain this new observation, without carefully considering the consequences of that on mechanism #1. When asked to explain the observation of the transit of Venus, we get mechanism #3 - which is that Venus orbits the FET sun, and it lit by it when it goes behind the sun and is dark when it crosses in front of it..
So now we have three mechanisms...but no connections between them...and here we get into trouble:
If the sun (due to it's brightness) is bigger than you'd expect at sunset (mechanism #2) - and it's position is closer to the horizon than you'd expect (mechanism #1) and the transit of Venus (mechanism #3) means that it's a dark circle while it's transiting the sun - THEN: Venus should appear much smaller when a solar transit happens at sunset than when it transits the sun at noon. That would be the logical conclusion from what you've told us.
Sadly, that's not what observations show. Venus appears to be exactly the same size (relative to the disk of the sun) regardless of when the transit happens.
So - either one of the three mechanisms #1,#2 or #3 is incorrect - or you need a new mechanism #4 to explain this new, easily observable fact.
But rather than try to come up with one - it's easier to say:
As we are empericists, the only acceptable empirical answer to this query is that the motions are visible to us, but the mechanisms are unknown.
That's a perfectly valid intellectual point of view - but it has to be applied consistently - and it isn't.
If you TRULY choose to simply catalog observations and consistently NEVER propose mechanisms - then (if intellectually honest) you wouldn't even be a "Flat Earther" - because your observations about the nature of what you see around you would not be formed into the "mechanism" that the earth must be flat - that the map of the world is as it is, that the sun and moon are 30 miles across and so forth.
Instead you'd simply catalog a bunch of common observations - and leave it at that.
This forum is full to overflowing with simple everyday observations that contradict your existing "mechanisms". If you choose to blow away all of your "mechanisms" - that's fine - or if you choose to follow the mainstream science approach of demanding continual effort to find (and fix) your mechanisms to account for every little anomaly you find - then that's a valid intellectual position too.
But to alternate randomly between "THIS IS DEFINITELY HOW IT WORKS" and "WE DON'T TRY TO EXPLAIN HOW IT WORKS" is not a philosophically tenable position.