Since the Earth is an ellipsoid, resultant forces of the Moon’s and Sun’s attractions are displaced from Earth’s mass center. Earth’s mass center cannot coincide with Earth’s center of rotation in a general case. A hypothetical observer, which is mentioned in the paper (division V) cannot observe a movement of the Earth’s axis of rotation on a cone surface with a peak in the Earth’s center. This Euler’s result was made in the XVIII century, but it is out field of vision of the contemporary astronomers.
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