Perhaps using pylons instead of sundials would convince the flat landers in your Facebook group of their misguided thinking. see: https://www.metabunk.org/soundly-proving-the-curvature-of-the-earth-at-lake-pontchartrain.t8939/
I arrived at this link via the Pylon of the Month website: https://www.pylonofthemonth.org/. It is the featured pylon for Oct. 2018. So, perhaps a whole bunch of sundials laid along the tops of pylons would provide a convincing experiment if you insist on using sundials. cheers..... Don Snyder On 6/17/2019 8:04 AM, Dan-George Uza wrote: Hello, In my country there is this growing Flat Earth movement akin to religious fundamentalism. No matter what you throw at them, they simply ignore it. There is even a big group on Facebook of about 5,000 users. I recently joined there for fun. First I thought they were joking, but everybody seems dead serious about it. I nearly got kicked out because my profile photo shows a large armillary sundial which they consider to be a globe.... So preposterous! :) So I recently wondered: can a sundial can be used to prove the Earth is round? And what would be the simplest gnomonic proof for this? Dan Uza --------------------------------------------------- https://lists.uni-koeln.de/mailman/listinfo/sundial
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