I just got back from the Wanderlust Festival in Vermont. My company, Slooh, wants to expand our audience. They thought it would be a great idea to do a Solstice and Full Moon program during a big yoga-type gathering.
I was skeptical, but I’d worried for nothing. The people were great, we got nice crowds for both our shows and it was an interesting format. I’d speak and do demos for ten minutes and then my partner would have a similar turn, leading meditations, chanting, sun salutations and the like. We kept switching off and, oddly enough, it went over well.
But a strange thing happened the moment we arrived. One of the staffers, a woman in her 40s, said, “You’re an astronomer? Have you heard? The Earth is actually flat! We’ve been lied to all these years!” Turns out there’s a growing interest in web documentaries that make the case for a flat Earth.
It made me wonder how to answer a person like her, convinced that the astronauts were all lying. Skepticism is a healthy thing. What if we didn’t have space probes that send us photographs of Earth? How could people know for sure?
Thanks to modern instantaneous global communication, I told her, you can settle this matter yourself. The next time you watch a sunset, phone a friend who lives to the east of you, or someone in a city to your west. Ask them where the sun appears in their sky. If Earth were flat, everyone would see the Sun setting at the same moment. But what you’ll actually find is that a friend living far enough east of you will report that it’s nighttime. A person well to your west is located around Earth’s curve and will report that the Sun is now fairly high in the sky. Case closed.
She looked at me blankly, so I continued: “Alternatively, you can use the logic of the ancient Greeks. Whenever the Full Moon ventures into the place in the sky that is opposite the Sun, which is where our planet’s shadow must lie, it goes into eclipse without fail. The shape of our shadow is always round. And while a disk or dish might also throw a round shadow, it would only do so when oriented perpendicular to the Sun. Most times the shadow would be oval. It could even be a straight black line. Instead, it’s round. And only a ball always throws a round shadow.”
She still seemed unconvinced. And after the long drive in silence, I was enjoying being pedantic. So I continued: “Yet another method is when you’re at the beach, notice that you only view the very tops of distant ships. Binoculars really help with this. You can clearly see that the ships’ bottoms are hidden by Earth’s curve.”
I recalled the math, which is amazing. When sitting on a beach chair with your eyes four feet above the sea, the horizon is just one-and-a-quarter miles away!
I remembered swimming in a large lake and holding my breath while lowering my head like a crocodile until my eyes were just inches above the surface. Sure enough, the far shore vanished. It was so cool. Even a lake is not flat! Its middle is curved higher than the shores, so it blocks out the other side if your eyes are low enough.
With all this, people should have realized Earth’s true shape millennia ago. Why did the wrong idea persist for so long? Why didn’t a “round Earth” appear in ancient texts like Homer’s Odyssey and the Bible?
Maybe you’re wondering what her reaction was to all this. She said, “I think I’ll watch that documentary again.” In other words, I had only confused her.
I am trying to learn “acceptance”: to feel okay that for many in our culture, science holds no attraction.
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