Ancient Cosmic Crashes May Have Altered Earth's Composition

Mysteriously, Earth's chemical composition is drastically different from that of the rocks that most likely helped to form the planet. Now, scientists think they may have an answer to this long-standing puzzle: The constant pummeling that formed Earth may have altered its composition. Among these, previous research found that enstatite chondrites have a mix of isotopes that is remarkably similar to that of Earth, which suggests they might be the raw material from which Earth originated.