A new study revealed that the displacement of magnetic fields, which last occurred 773,000 years ago, lasted for 22,000 years. The work is also capable of illuminating what is happening in the nucleus of our planet.
The Earth’s magnetic field has shifted several times during its lifetime; the north was south, the south was north. However, the way this change takes place remains largely a mystery. Scientists know that magnetic change took place about 773,000 years ago, but they don’t know exactly what makes the change in the nucleus of our planet. However, a new study may clarify the underlying cause. Because the study revealed that the magnetic change took place in a much longer time than expected.
In his articles published today in Science Advances, Brad Singer and his colleagues at Wisconsin-Madison University calculated that the Earth’s last magnetic change lasted for about 22,000 years. Previous studies have suggested that the incident lasted from 4,000 to 9,000 years. The new issue also reveals that change is more complicated than we thought.
The team used the data of the previous magnetic change called the Matuyama-Brunhes inversion to perform the calculation. One of the evidence found was in the lava. The iron-rich minerals found in the lava align with the Earth’s magnetic field before the lava hardens. Researchers also investigate the argon isotopes found in the lava, revealing how the lava was in a magnetic field before it became solid and could find its history.
The findings show that Earth’s magnetic field began to collapse about 795,000 years ago and began to experience what was known as a geomagnetic trip. The last geomagnetic trip event (Laschamp event) took place about 41,000 years ago. After slightly healed 784,000 years ago, the planet’s space collapsed again and ultimately changed the poles 11,000 years later. This change lasted 4,000 years.
Some scientists say that such a change is imminent. The consequences of such a change will be enormous on Earth. During a geomagnetic excursion or magnetic change, the magnetic field is significantly weakened and allows much more cosmic rays to reach the surface of the planet. These energy particles from space can damage life on Earth if they reach the surface too much. In addition, the orbiting satellites will become more susceptible to cosmic rays because they will not have the planet’s magnetic field to protect their sensitive electronics. So they’il get hurt. So the two poles in our world become a shield to us.
Determining the date of magnetic change can also reveal what is happening in the Earth’s nucleus. Singer explains this:
“Perhaps it is necessary to weaken the magnetic field strength for several thousand years to ensure magnetic change because the inner core is solid. If you disable the magnetic field of the liquid outer core, it will take several thousand years for the magnetic energy contained in the inner core to come out. ”
However, not everyone agrees with Singer’s findings. CEREGE’s Nicolas Thouveny says the evidence from the sediment core from the ocean floor indicates that the magnetic change lasts for up to 8,000 years. On top of that, lava does not provide reliable time data, he adds.
Singer, however, says that the lava flow data is verified in other observations. He even argues that Thouveny and his colleagues have failed to take into account the period before the magnetic change:
Iz Our findings clearly show that in the 22,000 years that have lasted until this short period, the external core dynamos have become quite unstable and have attempted to reverse the poles twice, 773,000 years ago. ”
In the future, further data analysis and discoveries about our kernel will help us calculate the timing. Perhaps even these discoveries will tell us the destiny of the planet’s magnetic field. Even nowadays, however, these studies are progressing very slowly because it is difficult to go down to the inner core. Therefore, we examine the materials that come out from the core.