I am very much a beginner on the astronomy front but I understand about planets having different axial tilts, hence why Venus turns the opposite direction from the Earth and Uranus turns sideways.
However, I am confused as to what the axial tilt bearing is measured from. For example, if all planets were in a perfect line from the sun, would they spin perfect in alignment on their own various axial tilts? Would some still be 'off-set' by a few degrees to one side or the other?
Do we actually know please?