Detecting the oldest geodynamo and attendant shielding from the solar wind: Implications for habitability

  title={Detecting the oldest geodynamo and attendant shielding from the solar wind: Implications for habitability},
  author={John A. Tarduno and Eric G. Blackman and Eric E. Mamajek},
  journal={Physics of the Earth and Planetary Interiors},
Abstract The onset and nature of the earliest geomagnetic field is important for understanding the evolution of the core, atmosphere and life on Earth. A record of the early geodynamo is preserved in ancient silicate crystals containing minute magnetic inclusions. These data indicate the presence of a geodynamo during the Paleoarchean, between 3.4 and 3.45 billion years ago. While the magnetic field sheltered Earth’s atmosphere from erosion at this time, standoff of the solar wind was greatly… 

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