Scientists Discovered the Age of Earth’s Magnetic Field

Without a magnetic field, it may have been hard for life to emerge on Earth as it has.

A new study has suggested that Earth’s magnetic shield is much older than it was previously thought, and is at least four billion years old.

For this particular study, a team of scientists examined four-billion-year-old zircon crystals – capable of surviving geological upheavals – from the Jack Hills region of Western Australia.

A team of researchers, having analyzed deposits from fires set by agricultural workers in the Iron Age in southern Africa (between 1000 and 1500 AD), say the data left by ancient ritualistic burnings of cleared-out villages show that the Earth’s magnetic field weakened dramatically in the past without flipping.

But as per the research, earth has been protected by the magnetic field from quite early in its history. It is believed to influence the direction of churning liquid iron that is known to disrupt the magnetic field, leading to a loss of magnetic intensity.

Without Earth’s magnetic field, solar winds – streams of electrically charged particles that flow from the sun – would strip away the planet’s atmosphere and oceans. When not writing or trying to read the entire internet, you’ll likely find him dancing, playing games, dabbling in creative stuff, or learning about whatever catches his eye. Today, that heat release is aided by plate tectonics, which efficiently transfers heat from the deep interior of the planet to the surface. Magnetite preserves a record of magnetic field strength at the time the mineral was trapped in the zircon.

Since 2010, the best estimate of the age of Earth’s magnetic field was 3.45 billion years. The new baked-clay records revealed an eerily familiar picture of the Earth’s magnetic field: Just like today, the Earth’s magnetic field at the time was steadily weakening, with a focus on that same South Atlantic Anomaly. Under those circumstances, he calculates that the maximum strength of a magnetic field would be 0.6?T (micro-Teslas).

Due to the rituals, the ground were burned up to 2,000 degrees Fahrenheit, causing the removal of magnetic traces stored in nearby magnetite and the formation of new magnetic fields.

“The top of the core beneath this region is overlain by unusually hot and dense mantle rock”, Dr Tarduno said.

“There has been no consensus among scientists on when plate tectonics began”, said Tarduno.

“It’s surprising, because some of the models of the ancient Earth suggest that a magnetic field or plate tectonics could not have occurred that early”, Tarduno said. If these storms hit during a time when the magnetic field was at its weakest, the effects would be exacerbated.

The age of Earth is estimated to be around 4.4 and 4.5 billion years old.

“It would be a pretty barren planet without it”, said University of Rochester geophysicist John Tarduno.

“It may also be a major reason why Mars was unable to sustain life”, he concluded.