# Earth (DD-131)

> Earth is not a perfect sphere but an oblate spheroid: its rotation flattens it at the poles and makes it bulge at the equator. The equatorial diameter is about 43 km greater than the polar diameter. Because of the bulge, the point on Earth's surface farthest from its center is the summit of Chimborazo in Ecuador, not Everest. The footage shows Earth from space, with the presenter.

- Department: Space (also Science)
- First published: 2023-12-20
- Last updated: 2023-12-20
- Permalink: https://detailenjoyer.com/case/earth/
- Author: Marcus Easterling (DetailEnjoyer), The Detail Department

## Quick facts

- **DD-131-F01**: Earth is an oblate spheroid. _(Write-up · Exhibit A (Oblate spheroid))_
- **DD-131-F02**: Its rotation causes the bulge. _(Write-up · Exhibit B (Rotation))_

## Write-up

Earth is about 43 km wider than it is tall. Its spin flattens it into an oblate spheroid.

1. **Oblate spheroid**: Earth is an oblate spheroid.
2. **Rotation**: Its rotation causes the bulge.
3. **43 km**: The equatorial diameter is about 43 km greater.
4. **Chimborazo**: Chimborazo's summit is farthest from Earth's center.
5. **Not a sphere**: The flattening is slight, about 0.3%.

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## Reel vs. record

- **Note**: None needed.

## Video: Earth: Earth Is About 43 km Wider Than It Is Tall

- Duration: 23.9 s · Published: 2023-12-20
- File: https://detailenjoyer.com/assets/videos/C1FKOQyOCfj.mp4

### Transcript

Earth our home planet is not a perfect sphere. DID YOU KNOW? It's slightly flattened at the poles and bulging at the equator due to its rotation. This shape is known as an oblate spheroid, the equatorial diameter is larger the diameter measured from pole to pole. This phenomenon results from the Earth's rotation causing a slight outward force at the equator and making it not a perfect sphere. This subtle distortion in shape is a fascinating aspect of our planet's NOW YOU KNOW!

## Questions & answers

**Q: What shape is Earth?**  
A: Flattened at the poles. _(Source: Write-up · Exhibit A (Oblate spheroid) · Wikipedia: Earth; Wikipedia: Equatorial bulge)_

**Q: What causes the bulge?**  
A: Spin pushes the equator out. _(Source: Write-up · Exhibit B (Rotation) · Wikipedia: Equatorial bulge)_

**Q: How much wider is Earth at the equator?**  
A: Diameter difference. _(Source: Write-up · Exhibit C (43 km) · Wikipedia: Equatorial bulge)_

**Q: Which summit is farthest from Earth's center?**  
A: Thanks to the bulge. _(Source: Write-up · Exhibit D (Chimborazo) · Wikipedia: Equatorial bulge)_

**Q: How big is the flattening?**  
A: Slight. _(Source: Write-up · Exhibit E (Not a sphere) · Wikipedia: Equatorial bulge)_

## Sources

- [Wikipedia: Earth](https://en.wikipedia.org/wiki/Earth)
- [Wikipedia: Equatorial bulge](https://en.wikipedia.org/wiki/Equatorial_bulge)

## Cite this case file

Easterling, Marcus. "Earth." The Detail Department (DetailEnjoyer), case file DD-131, last updated Dec 20, 2023. https://detailenjoyer.com/case/earth/