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In the most objectionable video, Fr. correctly explains that the sun in the image above (which is a favorite of flat-earthers) cannot illuminate one half of the earth with a pattern that transitions from day to night that is a straight line across the "flat" earth (as it does in observed reality everywhere we look). The "flat-earth" model requires the sun's projection of light to be necessarily circular in pattern as the model he displayed (like the one above) shows.
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The sun's light pattern on the "flat"earth is consequently circular, as shown by the yellow region surrounding it. He then says that the duration of daylight in such a model is always a period of 6 hours, whereas in fact, the length of day varies according to season and position on the earth's surface which contradicts the "flat-earth" model.
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There are numerous contradictions between observed reality and the "flat-earth" model.
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