Now that humanity knows quite positively that the moon is not a piece of cheese or a playful god, the phenomena that accompany it (from its monthly cycles to lunar eclips… See more

If you’ve been next to a port lately, or just strolled down a beach and stared off vacantly into the horizon, you might have noticed a very interesting phenomenon: Approachin… See more

This observation was originally made by Aristotle (384-322 BCE), who declared the Earth was round judging from the different constellations one sees while moving away from the eq… See more

If you stick a stick in the (sticky) ground, it will produce a shadow. The shadow moves as time passes (which is the principle for ancient Shadow Clocks). If the world had been flat, th… See more

Standing on a flat plateau, you look ahead toward the horizon. You strain your eyes, then take out your favorite binoculars and stare through them, as far as your eyes (with the he… See more