Reading this reminded me that the ancients have understood and applied celestial navigation, tides, eclipses, and scores of other concepts since at least Hipparchus around 2200 years ago. And before him, Eratosthenes measured the Earth's circumference to within 1.4 percent.<p>And now we have trolls and morons trying to undo human knowledge to before this point. I sat on my hands before going off to tilt at that windmill.