The Case Against Kyrie Irving’s Flat Earth Theory
“This is not even a conspiracy theory. The Earth is flat. The Earth is flat. … It’s right in front of our faces. I’m telling you, it’s right in front of our faces. They lie to us.”
Those were the words of Cleveland Cavaliers point guard Kyrie Irving on the Road Trippin’ with RJ & Channing podcast with teammates Richard Jefferson and Channing Frye.
Believe it or not, this was a commonly accepted belief by Greece, India and China until the 17th century. The first rumblings about the earth having a spherical shape was first introduced in the 6th century BC, with Aristotle officially providing evidence to stake the claim around 330 BC.
Irving remains unconvinced. And there’s precedent, at least for him personally.
“I’ve seen a lot of things that my educational system has said that was real that turned out to be completely fake. I don’t mind going against the grain in terms of my thoughts.”
It’s been more than a decade since the last time I studied planetary sciences, but no matter where you look, there is plenty of scientific evidence to debunk Irving’s frivolous and rather uneducated comment. Here are just a few things to consider:
During his studies, Aristotle noticed that during lunar eclipses — when earth’s orbit places the planet directly between the sun and moon — the shadow on the moon’s surface was round.
In the sequential view of the April 2014 lunar eclipse, you can see earth’s shadow clearly crossing the face of the moon. The shadow of earth’s shape is curved because the planet is a sphere.
In his book On the Heavens, Aristotle wrote: “Again, our observations of the stars make it evident, not only that the Earth is circular, but also that it is a circle of no great size. For quite a small change of position to south or north causes a manifest alteration of the horizon.”
Quite simply, you’ll see a different set of stars in the night sky depending where on the planet you are. The sky over the northern hemisphere is not the same sky over the southern hemisphere. If earth was flat, we’d all be looking at the same sky at any given time, and we’re not.
Another Greek thinker and mathematician, Eratosthenes, managed to measure earth’s circumference.
He discovered that on one particular day at noon in one Egyptian city, the sun was directly overhead. However, in another city he visited, the sun hadn’t risen so high. Eratosthenes knew the distance between the two cities, measured how high in the sky the Sun rose to in each at the same time, then did some trigonometry. His method was crude, but his answer was in the right ballpark.
The Center of Gravity
The most interesting fact about mass is that it attracts things to itself. The force of attraction (gravity) between two objects depends on their mass and the distance between them. Simply said, gravity will pull toward the center of mass of the objects. To find the center of mass, you have to examine the object.
Since a sphere has a consistent shape, no matter where you stand on it, you have exactly the same amount of sphere underneath you. A sphere’s center of mass is in the center of the sphere, meaning gravity will pull anything on the surface toward the center, no matter where it’s located.
On a flat plane, the center of mass is in its center, leaving the force of gravity to pull anything on the surface toward the middle of the plane. This means if you stood on the edge of the plane, gravity would pull you toward the center, not down as experience on earth.
And finally, if this isn’t enough for you, there’s a more interactive and educated approach to take: buy yourself a telescope and look up.