Meteorites: What are they and where do they come from?
What do meteorites contain?
Downloadable information
Calculator for the chances of finding or being hit by a meteorite.
Meteorites: What are they and where do they come from?
Meteorites are rocks from space. The majority come from the asteroid belt, which is between Mars and Jupiter, and are sent in our direction as debris from impacts.
Image obtained from NASA
Some meteorites also come from Mars or the Moon, though these are rarer since the debris has to escape the their much greater gravity.
Asteroids are remains from the creation of the solar system 4,500 million years ago. Consequently meteorites contain material from the early stages of the solar system history.
They can be divided into 3 groups:
Irons, stony-irons, and stones.
These categories can be subdivided depending on the constituents and their mineralogy.
The most common type of meteorite is a subcategory of stones known as chondrites. These are made up of very small spheres called chondrules. Chondrules were molten droplets and are the remains of the oldest material in the solar system. The chondrules accreted to form the first asteroids, some of which came together to make the planets we know today.
This is a photograph of a meteorite called Baratta taken in reflected light.
X-ray mapping produces images showing the distribution of elements. These allow us to identify minerals and their distribution. See the images below of meteorite called Parnalee to see how the minerals relate to chondrules.
 |
 |
X-ray map of silicate minerals. These are: blue: olivine purple: pyroxene green and yellow: feldspathic glass bright red: iron metals and sulphides (see image on the right) |
X-ray map of metals. These are: bright red: iron-nickel metal purple: iron sulphide green: phosphates |
Calculator for the chances of finding or being hit by a meteorite.
Scottish Meteorites
Carbonaceous Chondrites
CI Chondrites
CM Chondrites