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Gary Bainbridge
King’s Lynn, Norfolk, UK
In the recent conjectures about a flat planet, the correspondents so far have ignored the fact that the planet might be rapidly spinning. Indeed, that would be essential for a flat planet to form.
Assuming my maths is correct, a flat planet with the same volume as Earth and with a top surface the same area as the surface of Earth would be 25,482 kilometres in diameter, but only about 2000 kilometres thick.
For a person to be able to stand anywhere on the surface, the planet would have to rotate once every 37 minutes, but the effect on that person’s weight would be interesting. An average person standing at the centre of the planet would weigh some 2.8 tonnes, but standing at the edge, would weigh just 1.4 kilograms.
David Strachan
Llanbister, Powys, UK
In describing the curious effects of gravity as one moves across the surface of a flat, uniformly thick planet, especially towards the edges, your contributors have overlooked the mass of the four giant elephants that support it as it drifts through space on the back of the massive turtle (with thanks to the late Terry Pratchett).
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