There are various hypotheses on the formation of Earth and its moon, the majority of which involve a massive impact. Researchers from the Universities of Leeds and Chicago have now examined the fluid dynamics and electrically conducting fluid dynamics and come to the conclusion that the Earth must have been magnetized either prior to or as a result of the impact.
They contend that this may serve to clarify existing hypotheses regarding how the Earth and moon formed and guide future investigations into what actually transpired. Proceedings of the National Academy of Sciences have published their work.
Professor David Hughes, an applied mathematician at the University of Leeds’ School of Mathematics, said, “Our innovative theory asserts that what we currently know theoretically about the Earth’s magnetic field can actually teach us something about how the Earth-moon system originally came into existence. This may appear unexpected at first, and prior ideas did not account for this potentially significant connection.”
This updated evaluation is based on the Earth’s magnetic field’s resilience, which is preserved by a geodynamo, a revolving fluid that conducts electricity in the outer core.
University of Chicago astronomer Fausto Cattaneo noted that the Earth’s dynamo has the odd ability to retain a strong magnetic field but is unable to magnify a weak one.
The researchers came to the conclusion that the Earth’s magnetic field would not be able to turn on again even if it were to be completely turned off or lowered to a very small level.
Professor Cattaneo continued, “It is this amazing trait that allows us to draw conclusions about the history of the early Earth, including, perhaps, how the moon was formed.
Prof. Hughes continued, “If that’s the case, you’re forced to consider where the Earth’s magnetic field originated in the first place. Our theory is that it reached this odd state long ago, either prior to the collision or as a direct result of the impact. In either case, magnetic field evolution is a necessary component of any accurate model of the creation of the Earth-moon system.”
