## What is the circumference of the Earth for kids?

Quick Facts

Ninja Column 1 Ninja Column 2
Equatorial Circumference: 40,030 km
Polar Diameter: 12,714 km
Equatorial Diameter: 12,756 km
Mass: 5,972,190,000,000,000 billion kg

How was Earth’s circumference first determined?

Eratosthenes erected a pole in Alexandria, and on the summer solstice he observed that it cast a shadow, proving that the Sun was not directly overhead but slightly south. Recognizing the curvature of the Earth and knowing the distance between the two cities enabled Eratosthenes to calculate the planet’s circumference.

### When was the circumference of the Earth first discovered?

240 B.C. Eratosthenes Measures the Earth. By around 500 B.C., most ancient Greeks believed that Earth was round, not flat. But they had no idea how big the planet is until about 240 B.C., when Eratosthenes devised a clever method of estimating its circumference.

What is the circumference of the Earth?

24,901 miEarth / Circumference
In 200 B.C. Eratosthenes estimated Earth’s circumference at about 46,250 kilometers (28,735 miles). Today we know our planet’s circumference is roughly 40,000 kilometers (24,850 miles).

## Who figured out the circumference of the Earth?

Eratosthenes
This illustration shows how Eratosthenes actually calculated the circumference of the Earth. At noon on the summer solstice, Eratosthenes measured the length of the shadow cast by a column of known height at Alexandria. With these two lengths, he could solve for the angle between them (θ).

What is Earth explained to kids?

Earth is one of the eight planets that orbit, or travel around, the Sun in the solar system. It is the third planet from the Sun. Earth travels around the Sun at an average distance of about 93 million miles (150 million kilometers). It appears bright and bluish when seen from outer space.

### Who discovered the circumference of the earth?

What is so interesting about the Earth’s circumference?

The circumference of the Earth is just its average diameter, 7915 miles, times the number pi, where pi is 3.14159. This gives us about 25,000 miles for the Earth’s circumference. So Eratosthenes only missed the circumference by approximately 4 percent. This was truly remarkable precision for 2200 years ago.

## Who discovered circumference of Earth?

Why is circumference important?

Because the circumference measures a distance around something, it’s an invaluable tool for lots of work that involves area, shape, and measurement.

### How was the circumference of a circle discovered?

Archimedes envisioned a hexagon inscribed within a circle with radius ½. The formula for circumference is 2πr. Hence, with ½ as a radius, the circumference of his circle would be π. He then conjectured that the hexagon’s perimeter would approach the circumference of the circle (π).

What are 5 interesting fact about Earth?