Understanding Meteorite Entry into Earth's Atmosphere
When meteorites enter the Earth's atmosphere, they encounter varying layers of air, each with different characteristics. The layer where most meteorites burn up is the **mesosphere**.

What is the Mesosphere?
- The mesosphere is the third layer of Earth's atmosphere, located above the stratosphere and below the thermosphere.
- It extends from approximately 50 to 85 kilometers (31 to 53 miles) above the Earth's surface.

Why Do Meteorites Burn Up in the Mesosphere?
- **High Altitude:** As meteorites enter the atmosphere, they travel at extremely high speeds (often exceeding 25,000 miles per hour). By the time they reach the mesosphere, they are still moving fast enough to generate intense friction with the air molecules.
- **Temperature Increase:** The friction leads to rapid heating. In the mesosphere, temperatures can drop significantly, but the energy generated from the meteorite's speed creates heat intense enough to cause it to glow and eventually disintegrate.
- **Protection from the Stratosphere:** The stratosphere, located below the mesosphere, is where commercial airplanes fly. It is less dense but doesn't provide sufficient friction to burn up large meteorites effectively.

Conclusion
In summary, meteorites predominantly burn up in the mesosphere due to the combination of high velocity, resulting friction, and the thermal dynamics of this atmospheric layer. This phenomenon is why we often see "shooting stars," which are actually meteors disintegrating in the mesosphere.

Meteorites burn up in the mesosphere, which lies above the stratosphere and extends up to a height of 80 km.