20 Reasons We Know the Earth Is Spherical

Re:20 Reasons We Know the Earth Is Spherical by chopin on Thursday June 14, 2018 @09:36AM (#17311552)

Some of the reasons are not very compelling. Some thoughts:

4. Other planets are spherical: This rests on the premise that earth is also a planet. This is also the problem with no. 5.

8. Shadows of sticks: The earth could be flat and the sun could be small and close.

11. Gravity: This requires that the law of gravity can be derived independently from the fact that the earth is spherical. That's not easy.

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Re:20 Reasons We Know the Earth Is Spherical by psalminen on Thursday June 14, 2018 @11:54AM (#17312570)

> 11. Gravity: This requires that the law of gravity can be derived independently from the fact that the earth is spherical. That's not easy.

This can be done by observing the motions of other planets/moons/stars/galaxies.

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