Meteor, Meteorite, Asteroid: What's the Difference?
by AMNH on
News reports and YouTube videos of a meteor breaking up in the Siberian sky are pouring in. Tonight, another space rock—asteroid 2012 DA14—will fly by Earth more closely than any asteroid whose orbit astrophysicists have calculated beforehand.
What's the difference between a meteor, a meteorite, and an asteroid?
In the Museum's Arthur Ross Hall of Meteorites, curated by Denton S. Ebel, chair of the Division of Physical Sciences (Earth and Planetary Sciences), the differences are clearly explained. There, you can also see large fragments of the Cape York meteorite, including a 34-ton section known as Ahnighito.
The text below is adapted from the writing in the hall.
WHAT IS A METEOR?
Meteors are not meteorites. Like meteorites, meteors are objects that enter Earth’s atmosphere from space. But meteors—which are typically pieces of comet dust no larger than a grain of rice—burn up before reaching the ground. As they vaporize, they leave behind the fiery trails sometimes called “shooting stars,” even though meteors are not really stars. The term “meteorite” refers only to those bodies that survive the trip through the atmosphere and reach Earth’s surface.
WHAT IS A METEORITE?
In simplest terms, a meteorite is a rock that falls to Earth from space. The vast majority of meteorites are pieces of asteroids, the small rocky bodies that orbit the Sun mostly between Mars and Jupiter.
WHAT ARE ASTEROIDS?
Asteroids are rocky bodies found mostly in the asteroid belt, between Mars and Jupiter. Jupiter is the largest planet in our solar system, and its gravity is very strong. Asteroids, which are much smaller than planets, are sometimes pulled out of the asteroid belt by the force of Jupiter’s gravity. Many of these asteroids then travel toward the inner solar system—where they can collide with Earth.
For more about the asteroid flyby, and space rocks of all kinds, take part in a live Twitter chat with Dr. Ebel, this Friday, February 15, at noon ET. Post your questions here or use hashtag #asteroidchat on Twitter.