Astrophysicist and television show host Neil deGrasse Tyson has discredited the flat Earth theory, blaming its rise on the freedom of speech and on a faulty educational system.
In a new YouTube video posted March 9 on the StarTalk channel, Tyson explains his argument to co-host and stand-up comic Chuck Nice. To support his point that the Earth is truly round, he mentions various evidence, some from ancient Greeks and others from more recent space observations.
What Is The Flat Earth Theory?
Flat-earthers follow the empirical approach in forming their belief. Instead of relying on existing theories, they use their own senses to observe their environment to understand the planet's true nature.
Members of the movement believe that since the ground and the bottom of the clouds are flat, then it means the Earth is not round as what proponents have taught.
An example of a flat Earth proof is a study that was repeatedly conducted over a body of water stretching for an average of six miles. Known as the Bedford Level Experiments, it concludes that the water surface is not flat and therefore, doesn't match up with the existing theory that the planet is round.
Evidence That The Earth Is Round
Tyson opened the nine-minute show by mentioning the most obvious proof of all, a video taken from space that shows the planet as a rotating sphere.
The astrophysicist then went on to joke that "something doesn't square" as there are plenty of people who claim the sun, moon, and other planets to be round but not the Earth. He disproved this idea by pointing out that due to the way energy behaves, plus the laws of physics, the universe naturally forms spherical bodies.
Although some of them may turn out a little distorted because they rotate too fast, almost everything found in the universe is spheres, except for asteroids and some other few.
Tyron added that another evidence of the planet's round curvature can be seen during lunar eclipses. If the Earth was indeed flat, then its shadow should appear flat as well. Instead, a perfectly round shadow is cast during such phenomenon.
Ancient Greek Experiment By Eratosthenes
Furthermore, he talked about an experiment conducted by Eratosthenes back in 250 B.C. Upon observing wells in two different cities during summer, he notes that the bottom of the well in Syene can be seen clearly during noontime. Meanwhile, at the same time of the day, the well in Alexandria was still so full of water that its bottom is not visible at all.
Tyson gave two explanations for this. First, that the planet is round with a sun located at a farther distance. Second is that the planet is flat but only has a small sun. Based on the results, however, the flat Earth explanation is not possible.
Neil deGrasse Tyson's Message To Flat-Earthers
If there is anything that flat-earthers prove, Tyson identified that it's the current educational system's failure to teach critical analysis to students.
"Our system needs to train you not only what to know but how to think about information and knowledge and evidence," he says, addressing believers of the flat Earth theory. "If we don't have that kind of training, you'd run around believing anything."
The discussion featured in the video is based on a chapter included in Tyson's book Astrophysics for People in a Hurry.