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Account for what? The ephemeris that calculated those coordinates is based on orbital parameters of planets with elliptical orbits around the centre of mass. If the planetarium software shows it happing then clearly it cannot be impossible in the model.
>This would be physically impossible...
Which of course is not motivated at all.
The only clue given to the retarded though process is an grasp at parallax, but really the orbital diagram shows you expect no apparent "parallax". The motion of planets through the night sky is a combination of parallax and motion, it isn't somehow impossible for those things to almost cancel out. Parallax is apparent in the retrograde motion of Mars.
