1) Is it theoretically possible in a universe of two planetary objects - a Sun in a fixed position and a planet of any other finite mass, for that planet to orbit the sun in a perfectly circular orbit (not an ellipse?)(adsbygoogle = window.adsbygoogle || []).push({});

2) Are the elliptical (or near elliptical) orbits that occur in the real world due to the perturbations of forces exerted on the planet which throw it "off" a perfect circle and once an imbalance is created the new balance is an ellipse?

3) Is the precession of the perihelion and aphelion of mercury about the Sun due to the increased mass of mercury (old term "relativistic mass") as it increases in velocity as it approaches its perihelion and thus forces the center of gravity or center of mass of the combined objects of the Sun and mercury to shift outward and thus force an almost imperceptible but present movement of the mercury-Sun dyad outward and thus the orbit to migrate?

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# Elliptical Orbits (Using Newton's Model)

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