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posted by janrinok on Tuesday June 08, @07:45PM   Printer-friendly
from the off-balance-Betteridge dept.

Is Earth's core lopsided? Strange goings-on in our planet's interior.:

For reasons unknown, Earth's solid-iron inner core is growing faster on one side than the other, and it has been ever since it started to freeze out from molten iron more than half a billion years ago, according to a new study by seismologists at the University of California, Berkeley.

The faster growth under Indonesia's Banda Sea hasn't left the core lopsided. Gravity evenly distributes the new growth — iron crystals that form as the molten iron cools — to maintain a spherical inner core that grows in radius by an average of 1 millimeter per year.

But the enhanced growth on one side suggests that something in Earth's outer core or mantle under Indonesia is removing heat from the inner core at a faster rate than on the opposite side, under Brazil. Quicker cooling on one side would accelerate iron crystallization and inner core growth on that side.

This has implications for Earth's magnetic field and its history, because convection in the outer core driven by release of heat from the inner core is what today drives the dynamo that generates the magnetic field that protects us from dangerous particles from the sun.

"We provide rather loose bounds on the age of the inner core — between half a billion and 1.5 billion years — that can be of help in the debate about how the magnetic field was generated prior to the existence of the solid inner core," said Barbara Romanowicz, UC Berkeley Professor of the Graduate School in the Department of Earth and Planetary Science and emeritus director of the Berkeley Seismological Laboratory (BSL). "We know the magnetic field already existed 3 billion years ago, so other processes must have driven convection in the outer core at that time."

(...) Asymmetric growth of the inner core explains a three-decade-old mystery — that the crystallized iron in the core seems to be preferentially aligned along the rotation axis of the earth, more so in the west than in the east, whereas one would expect the crystals to be randomly oriented.

Evidence for this alignment comes from measurements of the travel time of seismic waves from earthquakes through the inner core. Seismic waves travel faster in the direction of the north-south rotation axis than along the equator, an asymmetry that geologists attribute to iron crystals — which are asymmetric — having their long axes preferentially aligned along Earth's axis.

Journal Reference:
Daniel A. Frost, Marine Lasbleis, Brian Chandler, et al. Dynamic history of the inner core constrained by seismic anisotropy, Nature Geoscience (DOI: 10.1038/s41561-021-00761-w)

Also at Nature

Original Submission

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  • (Score: -1, Troll) by Anonymous Coward on Tuesday June 08, @08:49PM (3 children)

    by Anonymous Coward on Tuesday June 08, @08:49PM (#1143272)

    This means you'll have to eat the bugs, wear the mask, get the vaccine, live in pods, and become utter slaves to climate tax!

    China and India? Who cares what they do, Jewish politicians are profiting handsomely from them, so maybe we should just mind our own business instead. Don't forget your 2021 commemorative vaccine and climate change tattoos to show everybody else that you're fighting the good fight!

    Starting Score:    0  points
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  • (Score: 0, Informative) by Anonymous Coward on Tuesday June 08, @09:40PM

    by Anonymous Coward on Tuesday June 08, @09:40PM (#1143278)

    We're coming for your capital gains, Chuck! We are going to slave you, and if you don't like it, we will force you to wear a mask and be politically correct. And then we will restrain you, using the extra fine strainer we use for applesauce. And then, we will force you to understand the basics of science, logic, and ethics, by slaving you into college. And you will LIKE it, and you will thank us later, when you are better. Some of us are Jews, but all of us are Americans, and you are failing to live up to standards.

  • (Score: 2, Informative) by Freeman on Tuesday June 08, @09:43PM (1 child)

    by Freeman (732) on Tuesday June 08, @09:43PM (#1143281) Journal

    Too late! They've already started accustoming the public to pod spaces! []

    Forced Microsoft Account for Windows Login → Switch to Linux.
    • (Score: 3, Funny) by shortscreen on Wednesday June 09, @12:09AM

      by shortscreen (2252) Subscriber Badge on Wednesday June 09, @12:09AM (#1143331) Journal

      I was assuming most people already lived in pods. It's the only explanation for why they would be forced to get by with a smartphone instead of a real computer. Isn't it?