New Research Provides Evidence of Strong Early Magnetic Field Around Earth 16
New research from the University of Rochester provides evidence that the magnetic field that first formed around Earth was even stronger than scientists previously believed. The research, published in the journal PNAS, will help scientists draw conclusions about the sustainability of Earth's magnetic shield and whether or not there are other planets in the solar system with the conditions necessary to harbor life. Phys.Org reports: Using new paleomagnetic, electron microscope, geochemical, and paleointensity data, the researchers dated and analyzed zircon crystals -- the oldest known terrestrial materials -- collected from sites in Australia. The zircons, which are about two-tenths of a millimeter, contain even smaller magnetic particles that lock in the magnetization of the earth at the time the zircons were formed. Previous research by [John Tarduno, Professor of Earth and Environmental Sciences and Dean of Research for Arts, Sciences, and Engineering at Rochester] found that Earth's magnetic field is at least 4.2 billion years old and has existed for nearly as long as the planet. Earth's inner core, on the other hand, is a relatively recent addition: it formed only about 565 million years ago, according to research published by Tarduno and his colleagues earlier this year.
While the researchers initially believed Earth's early magnetic field had a weak intensity, the new zircon data suggests a stronger field. But, because the inner core had not yet formed, the strong field that originally developed 4 billion years ago must have been powered by a different mechanism. "We think that mechanism is chemical precipitation of magnesium oxide within Earth," Tarduno says. The magnesium oxide was likely dissolved by extreme heat related to the giant impact that formed Earth's moon. As the inside of Earth cooled, magnesium oxide could precipitate out, driving convection and the geodynamo. The researchers believe inner Earth eventually exhausted the magnesium oxide source to the point that the magnetic field almost completely collapsed 565 million years ago. But the formation of the inner core provided a new source to power the geodynamo and the planetary magnetic shield Earth has today.
While the researchers initially believed Earth's early magnetic field had a weak intensity, the new zircon data suggests a stronger field. But, because the inner core had not yet formed, the strong field that originally developed 4 billion years ago must have been powered by a different mechanism. "We think that mechanism is chemical precipitation of magnesium oxide within Earth," Tarduno says. The magnesium oxide was likely dissolved by extreme heat related to the giant impact that formed Earth's moon. As the inside of Earth cooled, magnesium oxide could precipitate out, driving convection and the geodynamo. The researchers believe inner Earth eventually exhausted the magnesium oxide source to the point that the magnetic field almost completely collapsed 565 million years ago. But the formation of the inner core provided a new source to power the geodynamo and the planetary magnetic shield Earth has today.
Age of the core (Score:4, Informative)
Citation: Wikipedia "Earth's inner core" https://en.wikipedia.org/wiki/... [wikipedia.org]
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Honestly, it doesn't sound like they're discovering something so much as finding evidence that their old ideas were wrong, and so they're spitballing.
Which is how it is supposed to work. Don't tell the journalists.
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Cue the Electric Universe loonies though. I'm sure that the comments on this article at Phys.org are full of them.
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Only half the claims commonly included under the umbrella term "Electric Universe" are falsifiable.
In the cases where they make an alternate non-falsifiable claim than astrophysics makes, it is irrational to believe either of them. It is more rational to lump all that shit into "unknown" or "probably not knowable."
If they don't agree with Einstein's math, that's obviously not going to end well for them, but that shit is testable.
But all sorts of large scale, observational stuff could be totally and easily w
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My favorite EU claim is that the Sun is actually heated by the stream of electrons flowing into it from the wider universe, not by gravitational heating or fusion. Whey asked why no one has ever observed the enormous electron flux that would require in spite of having scores of instruments in space that could detect it they declare that it's a conspiracy of tens of thousands of scientists worldwide who are getting rich off their faked research.
I only learned recently that Velekovsky was one of the originat
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You can't discover a new power source that conveniently pollutes some part of spacetime we can't easily access without nutters, though.
Serendipity is an important part of the process, so asking stupider and stupider questions can turn out to have a lot of value in the end.
As a natural philosopher, not a scientist, I can see the value they bring to the table, and I commend them on their personal sacrifice since they're giving up the ability to understand what is understandable about Nature.
We know that perpe
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Given the vital nature that the magnetic field plays in the development of higher life forms, did the researchers (or peers) correlate the short-term drop in the magnetic field 565 million years ago with a corresponding decrease in higher-form diversity in the fossil record? The collapse of the magnetic field on Mars likely doomed it as a home for flourishing life - it would be nice to see what evidence there is for its affect on Earth.
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Huh - I thought primitive plants preceded animals.
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Pneumodesmus newmani (early millipede) - It was originally interpreted as living 428 million years ago, in the Late Silurian;[1][2] however, the study conducted by Suarez et al. (2017) indicates that it actually lived in the Early Devonian (Lochkovian).[3] [wikipedia.org]~416.8 Mya
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I knew It! (Score:3)
"and analyzed zircon crystals"
Even that time Svarovski shops were everywhere.
Are humans a mutation? (Score:1)
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