Britannica Sources used in this answer

At what altitude do visible meteors usually begin to appear?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

Meteor and meteoroid The Cabin Creek meteorite, an iron (nickel-iron alloy) meteorite that was observed to fall in northwestern Arkansas on March 27, 1886. Its characteristic pattern of “thumbprint” dimples, or regmaglypts, is the result of melting and consequent ablation of its surface as it traveled through the atmosphere. The meteorite is likely a fragment of one of the M class asteroids, which show significant nickel-iron in their surface material.

A typical visible meteor begins to appear at an altitude of 100 km (60 miles) or higher.1

As a meteoroid enters Earth’s atmosphere at high velocity, friction with atmospheric gas molecules converts its kinetic energy into heat. Even at the low atmospheric density found at 100 km, this heat is sufficient to vaporize and ionize the surface of the object and the surrounding gas, creating the luminous streak known as a meteor.1