3 proofs that debunk flat-Earth theory | NASA's Michelle Thaller | Big Think

TL;DR

There are multiple proofs, such as seeing ships disappear over the horizon and measuring the angles of the sun, that confirm the Earth is round.

Transcript

So, Oscar, you asked the question, “What are some of the easiest ways that you can prove that the Earth is round?” Because apparently, this is something that we’re debating—I have no idea why. That’s a hard thing for me to even start talking about because there are so many proofs that the Earth is round, it’s difficult to know where to start. And i... Read More

Key Insights

• 🧑‍🚀 Personal testimonies and photographs from astronauts orbiting the Earth provide evidence of its roundness.
• 🚥 The disappearance of ship bottoms over the horizon exemplifies the curved nature of the Earth.
• 🛝 The accuracy of ancient Greek measurements supports the understanding of the Earth's round shape.
• 😓 The curved shadow cast during a lunar eclipse confirms the Earth's spherical nature.
• 💠 Comparing the shape of the Earth to other celestial bodies in the solar system emphasizes its roundness.
• 😅 The misconception of space being hot is clarified by the lack of air at high altitudes.
• 👻 Binoculars and telescopes allow us to observe other planets and celestial bodies, all of which are spherical.

Questions & Answers

Q: How can the disappearance of ships over the horizon prove the Earth is round?

As ships move farther away, their bottoms disappear before their tops due to the curvature of the Earth. This wouldn't happen if the Earth were flat.

Q: How did ancient Greeks determine the Earth's roundness?

A Greek scientist named Eratosthenes measured the angles of the sun in different cities and calculated the Earth's circumference accurately, indicating that the Earth is round.

Q: What happens during a lunar eclipse that shows the shape of the Earth?

During a lunar eclipse, the Earth casts a curved shadow on the moon, illustrating the roundness of the Earth.

Q: How did Aristarchus prove that the Earth is a sphere?

Aristarchus showed that the shadow cast by the Earth on the moon during a lunar eclipse is always curved, regardless of the angle of the sun, demonstrating the Earth's spherical shape.

Summary & Key Takeaways

• The Earth being round is proven by various facts, including personal experiences of astronauts, photographs from space, and ancient Greek proofs.

• The bottom of ships disappearing over the horizon shows the curvature of the Earth.

• The measurement of sun angles at different locations on Earth demonstrates its spherical shape.