> an ellipse in a circular gravity field coming from a point mass. Even if you c... | Hacker News

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		amelius on Oct 18, 2020 \| parent \| context \| favorite \| on: Gravity is not a force – free-fall parabolas are s... > an ellipse in a circular gravity field coming from a point mass. Even if you consider the point mass to move because of the mutual attraction?

nealabq on Oct 18, 2020 [–]

One foci of the ellipse is the earth+ball center of gravity. The earth is also travelling in a much smaller ellipse around that same foci.

Assuming a uniform+spherical earth. And also a uniform+spherical ball I supposed.

srtjstjsj on Oct 19, 2020 | [–]

*One focus, of the the two foci.

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