Access

News and Views

Nature 446, 623-625 (5 April 2007) | doi:10.1038/446623a; Published online 4 April 2007

Open Innovation Challenges

  • Single-cell Analysis Platform

    • Deadline: Dec 02 2009
    • Reward: $5,000 USD

    This Challenge is looking for novel approaches to analyzing changes at a single-cell level. This is...

  • Optimizing Sub-cellular Localization Tags

    • Deadline: Jan 31 2010
    • Reward: $20,000 USD

    The Seeker is looking for methods to optimize sub-cellular localization tags for protein expression....

Palaeomagnetism: A more ancient shield

David J. Dunlop1

Top

Earth's magnetic field has protected our atmosphere from erosion by the solar wind ever since it started up. Silicate crystals from some of Earth's oldest rocks date that event to more than 3 billion years ago.

Most planetary magnetic fields originate from the movement of electrically conducting fluid in the planet's interior: Earth's own magnetic dynamo lies deep in its hot, convecting core of liquid iron. The resulting global magnetic field protects Earth's atmosphere from depletion by the solar wind, a continuous, but highly variable, stream of charged particles ejected from the Sun.

  1. David J. Dunlop is in the Department of Physics, University of Toronto, Toronto, Ontario M5S 1A7, Canada.
    Email: dunlop@physics.utoronto.ca

MORE ARTICLES LIKE THIS

These links to content published by NPG are automatically generated.

RESEARCH

Geomagnetic field strength 3.2 billion years ago recorded by single silicate crystals

Nature Letters to Editor (05 Apr 2007)

Supplementary Information

Nature Geoscience Letter (01 Jun 2008)