What is a Meteorite?

What Is A Meteorite?
by Eric Wichman

Large NWA Chondrite Meteorite

If you’ve ever wanted to know what the difference between a meteorite, meteoroid, and meteor is, here are some basic facts in order of appearance.

A meteoroid floats through space until the Earth’s gravity pulls it into our atmosphere. Once it enters our atmosphere it begins to heat up due to the friction caused by the air resistance on the surface of the meteoroid. As it heats up it begins to glow and produce a fireball. This is a meteor. It then cools at an altitude of about 10km-30km. The meteor seems to disappear, but it’s still there falling through the air, but with no more fireball or visible trail. It then impacts the Earth’s surface. If it survives this impact it is now a called a meteorite.

DEFINITIONS: Meteorites Are Meteoroids Which Have Survived Impact With The Earth’s Surface.

Meteoroid: A natural object in space usually smaller than a few meters. Small particle sized pieces of planetary debris consisting primarily of stone type minerals and iron with some nickel. Small amounts of other minerals are present found in meteoroids. There a probably as many different types of meteoroids as there are minerals on our planet.

Meteor: The effect of a meteoroid entering earths atmosphere, caused by the friction of air resistance against the surface of the object, producing a visible fireball. Better known as a shooting star or a falling star. A large number of meteors in a short time is called a meteor shower. Also called a bolide.

Meteorite: A space-born natural rock that survives impact with the earths surface after entering earths atmosphere. The majority of meteorites are ordinary stone (chondrite) type rocks with some consisting of large amounts of nickel iron. A few (about 5%) are solid iron.

Asteroid: Asteroids are large natural bodies of rock in space. Larger than meteoroids, asteroids are huge in comparison, up to 100 kilometers or more in size. Also called planetoids. Asteroids are smaller than planets but some like the asteroid Ida actually have small moons which orbit the body.

Comet: Large bodies of loosely bound natural rock, ice and gas which orbits the Sun. Comets expel these gases producing a coma or tail consisting of small particles of trailing debris. This effect is caused by the solar radiation from the Sun, and intense heat. Comets follow orbits which bring the body close enough to Earth for us to view. These orbits range in time from Short-Period comets (a few years) to Long-Period comets (hundreds or thousands of years).