A streak of light crosses the night sky as a bit of extraterrestrial material falls to Earth.

Meteorites, which range from particles of dust to massive chunks of metal and rock, bombard the Earth constantly, adding hundreds of tons of new material to our planet each day. What are these objects? How do we recover and study them? Where do they come from, and what do they tell us about the birth and infancy of the solar system? Why do many scientists now believe that meteorites have played a dramatic, albeit occasional, role in the evolution of life on Earth?

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