Thousands of tonnes of rocky material enter
Earth’s atmosphere each year. Most of it
originates from asteroids, but some comes
from comets, the Moon, and even Mars.
As the rocky pieces close in on Earth they
are termed meteoroids. Most burn up, but
those that survive and land are known
as meteorites. There are three main types:
stony meteorites, iron meteorites, and
stony-iron meteorites – the rarest kind.Meteorites
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▼ ESQUEL
This stony-iron meteorite was
collected in Esquel, Argentina,
in 1951. Golden-coloured
crystals of the mineral
olivine are embedded
in the iron-nickel metal.▲ METEOR
Meteoroids burning up in Earth’s atmosphere
produce bright trails. These short-lived streaks of
light are termed meteors, or shooting stars. About
a million occur every day.BARWELL ▶
The Barwell meteorite is one
of a shower of stones that fell
in England in 1965. As it
plummeted through Earth’s
atmosphere, friction caused the
outer surface to heat and melt.
This later solidified into a black crust.◀ MURCHISON
Stony meteorites are the
most common. This one,
the Murchison, fell in Australia
in 1969. It is one of the most
studied meteorites and
contains minerals, water, and
complex organic molecules.THIEL ▶
The Thiel
Mountains stony-
iron meteorite
was one of the
first found in
Antarctica, in 1962.144_145_Meteorites.indd 144 10/01/19 2:26 PM