Since then, we have learned that many of these molecules can form even in the less chemistry-friendly environments of interstellar space, so lots of simple organic molecules may have arrived on Earth, ready-made, inside comets or asteroids. For example, the Murchison meteorite, which fell to Earth near Murchison, Australia, in 1969, contained amino acids and several of the chemical bases that we find in DNA. Such meteorites were much more common early in Earth’s history than they are today, which suggests that the early Earth was already seeded with many of the raw materials of life and quite
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