Our transcription: In addition to the nine familiar planets, between Mars and Jupiter there lies a belt of drifting rubble, the asteroids.
Fragments of rock are set free by collisions among these asteroids.
This is the source of most of the meteorites, which strike Earth in present geological time.
These rocks from the asteroid belt are over four and a half billion years old.
They are typically rich in silica, alumina, iron, and nickel.
Such elements are common inside the Earth.
The overall density of the Earth is also close to the average density of meteoritic material, so it seems likely that meteorites represent the same type of raw material, which accreted to form the Earth.
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