What is the Earth’s magnetic field?
The Earth’s magnetic field is the one that protect us from the potential of the dangerous solar radiations. According to the new findings, the Earth’s magnetic field is starting to lose from its stability. Different scientists agreed that the Earth’s poles have changed their position over time and several times until now, but they suspect that in the distant past, there were slightly chances for the poles to reverse. The Earth’s magnetic field is supplied from the heart of our planet, which means – that’s right – straight down from the center of the earth.
The center of the earth is, in fact, a mixture of a solid iron and nickel that are found at a temperature of up to 5000 Celsius grades. These are surrounded by a layer of molten rock, with the temperature reaching 2900 Celsius grades, which is hotter that it is at the bottom. A hot iron rises in the outer core, and then it cools down and sinks again. In combination with the Earth’s rotation, these convection currents are suspected to generate a geodynamic move that creates the magnetic field.
The Earth’s magnetic field changes
The magnetic field’s strength varies according to the changing of the temperatures and the flowing of the fluids, and also according to the positions of the north and the south magnetic poles, everything leading to its change. The changes that affect the Earth’s magnetic field can leave traces in the rocks. How is that possible? Well, because that when the lava starts cooling, the metal oxide particles begin to solidify and stabilize the rock in the direction of prevailing the magnetic field.
Scientists can determine the historical positions of the magnetic poles just by examining and studying samples of lava. This is how we found out that in the last 100 millions of years, there have been pretty much about 170 magnetic pole reversals. Also, it is believed that the last pole reversal happened pretty much about 78.100 years ago.
If nowadays, the new findings show that the Earth’s magnetic field is starting to lose its powers, then no one can know exactly what will happen when it weakens too much or actually disappear for a long period of time, at least during the reversal of the poles. However, scientists believe that electricity grids and communications systems could be affected.
But there is another thing that studies on the Earth’s magnetic field have revealed, which is the fact that it is powered by the magnesium trapped in the core of the planet, ever since its birth. Or at least this is a new theory that is making its way out on the surface.
Magnesium powers the magnetic field
We know about magnesium that it is the fourth most common element that can be found in the planet Earth’s outer layers, although at some point, some opinions of the scientists claimed that there was too little or almost not at all magnesium in the core of our planet. This speculation was based on the fact that iron and magnesium can’t or won’t easily mix up. This thing got scientists into thinking that the Earth’s core was made out mostly of iron.
But this speculation is past time, because recent theories got specialists into thinking more that the planet Earth has been born through a series of violent collisions that resulted from other protoplanets. During the collision of the protoplanets, the pressures and temperatures had reached such an intensity that the iron and the metal managed to combine in an alloy, or so it claims a study published in the Journal Nature. The authors of this study concluded also that when two planets smash into each other, their bodies could have injected magnesium into the core of the future planet Earth.
When investigating about the behavior of the magnesium in the core of the planet, the authors have reached to the following conclusion: during the time that the planet Earth’s core begun to cool down slowly, the magnesium-oxide minerals begun to “snow” out from the heart of the iron and nickel alloy. Thus, the solid magnesium “snow” appears to be lighter than it is the liquid metal. Also, this solid magnesium “snow” is believed to float outward through the outer core of the liquid metal, churning it and also empowering the convection that ultimately lead to the production of the known global magnetic field.
However, there is a big question that has been giving scientists headaches ever since the planetary science started out. The question whose answer triggered the interest and further investigations of the scientists all over the world refers to what exactly has been powering the planet Earth’s magnetic field for these past billions of years. A part of the scientists agreed that the process of the iron cooling and its solidification in the core of the planet Earth is what triggered the Earth’s magnetic field.
This movement is also known as geodynamo. But this opinion can’t quite explain the way that the Earth’s magnetic field has been generated even before the solid inner core started to form about one billion of years ago. This is why this new theory of the “metal snow” also known as magnesium started to kick in, providing an alternative theory concerning the source of the energy of the planet Earth’s magnetic field.
However, this new theory hasn’t been through too much testing and experimental exams, but at least is has the benefit of not needing to invent or look for crazy explanations of something that happened in the distant past and that still has effects on the present situation. So, one of the minuses of this new model theory is that it shows little evidence that can indicate or support how exactly does the magnesium behave when in contact with pressures and temperatures that are produced in the planetary collisions time.
So, while the big idea is set on screen and it enjoys a lot of appreciation and credibility, the small details still need to undergo tests and experiments in order for scientists to have a clearer and more accurate vision of how the metal snow empowers the planet Earth’s magnetic field.
If you’re wondering why a magnetic field is so important that people are trying so hard to discover how exactly it works, invest their time, energy and money into figuring it out, here is your perfect answer: the magnetic field of a planet is important because it sustains the life of every living creature, plant or thing on that planet. It acts like a shield for the planet and it is also a shield for the atmosphere from the solar wind.
If they come to know how old is the planet Earth and implicitly how old is the planet Earth’s magnetic field, they might estimate just for how long there has been life on our planet. Also, they can find out how they can help improve the lives of the current people residing on planet Earth. And most importantly, they can also search and inform themselves about whether there is life on other planets. This thought is what keeps scientists and researches going and developing further investigations.