by Playfuls Staff |
5th April 2007
U.S. geophysicists have determined the Earth's magnetic field was nearly as strong 3.2 billion years ago as it is [more] currently.
The finding, which is contrary to previous studies, suggests that even in its earliest stages, the Earth was well protected from the solar wind that can strip away a planet's atmosphere, allowing lethal levels of radiation to reach the surface.
"The intensity of the ancient magnetic field was very similar to today's intensity," said University of Rochester geophysics Professor John Tarduno. "These values suggest the field was surprisingly strong and robust. It's interesting because it could mean the Earth already had a solid iron inner core 3.2 billion years ago, which is at the very limit of what theoretical models of the Earth's formation could predict."
The research, co-authored by post-doctoral student Rory Cottrell and funded by the National Science Foundation, appears in the journal Nature.
© 2007 UPI
