Around 565 million years ago, Earth avoided a catastrophic collapse of its magnetic field.
According to a study published in Nature Geoscience, Earth’s ‘nucleation’ as it is referred to, led to a dramatic alteration in our planets magnetic field: Scientists found that it went from being extremely weak, erratic to a stable configuration we see today.
According to a group of scientists from Rochester University, led Richard Bono, our planet’s inner core solidified much later than previously expected, something that profoundly impacted our planet.
“The nucleation of the inner core may have occurred right in the nick of time to recharge the geodynamo and save Earth’s magnetic shield,” wrote experts.
Had the magnetic field collapsed, life on Earth would have had needed to overcome great challenges to come into existence.
Scientists say that without a magnetic field, the solar wind would have stripped our planet of its precious atmosphere, causing harmful solar radiation to bombard the surface.
However, our planet’s core solidified ‘right in the nick of time’, causing Earth’s magnetic field to recharge just when it was at its weakest point.
The new study may provide precious information about the formation of Earth’s core.
But it also backs up a standing scientific theory which suggests that our planet’s core is relatively young. Despite this, the “young core hypothesis” has several issues that need to be addressed.
The main issue with this theory is that Earth’s core should be much hotter than it is believed to be now. Experts argue that one solution to that issue is that more radioactive elements ended up in the core than initially thought. However, we also might have insufficient data about the core’s chemistry.
Going back in time
To make their discovery, experts studied single crystals of plagioclase and clinopyroxene which formed roughly 565 million years ago.
The data they gathered allowed them to accurately reconstruct the timeline of Earth’s nucleation.
What they found took them by surprise.
They discovered unprecedentedly low geomagnetic field intensities, which indicates there was a high frequency of magnetic reversals hundreds of millions of years ago, that points to the fact that the geodynamo was on the point of collapsing.
“An enduring mystery about Earth has been the age of its solid inner core,” the researchers wrote in their study.