Earth’s core is mostly comprised of molten iron, a ferromagnetic element. However, iron alone does not make for a great magnetic field. It turns out iron gets some pretty crucial help from an old, elementary fried—nickel.Let’s start with the bigger question. Why is Earth’s magnetic field so important? Simply put, if it weren’t for our planet’s magnetic field, we’d all be zapped by the sun’s radiation and any and all life would not exist. The magnetic field creates a barrier, one that solar wind cannot completely penetrate. Because these harmful rays never reach us, our atmosphere is able to thrive and provide some pretty essential components of life, like oxygen.
Another fun effect of Earth’s magnetic field? The aurora borealis and aurora australis—the northern and southern lights. These magical streams of colorful light dance across the polar skies because of light particles hitting our magnetic field.
How Earth’s Core Makes a Magnetic Field
Bringing things back down to Earth, let’s discuss how our magnetic field is generated in the first place. The magnetic field is possible because of the Earth’s dynamo effect—at least this is the leading theory. No one can say for sure. However, the dynamo theory states that because Earth’s core is made of molten (liquid) metal under immense pressure, it is essentially able to rotate deep underground. This rotation creates energy and heat. Because iron is ferromagnetic, Earth’s magnetic field can exist.However, there’s a bit more to it than that. According to findings reported by Laboratory News, Earth dynamo effect, and by extension its magnetic field would not exist without the presence of molten nickel as well.
What Can Nickel Do for You?
So what makes nickel such a special ingredient in Earth’s core? It all comes down to the humble little electron. In case you’re a little rusty on your junior high chemistry, electrons are subatomic particles that orbit the nucleus and provide an atom’s negative charge. What makes a nickel atom’s electrons so special is that they are more prone to scatter than those of an iron atom.
Again, what makes this a big deal? Because the electrons aren’t as tightly gathered in a nickel atom, it doesn’t have the same heat conductivity as iron or other heavier elements. This lowers the overall all thermal conductivity of the entire planet core. In other words, without nickel’s wandering electrons, things would be a lot hotter!
Because nickel cuts down on the thermal conductivity, this heat cannot escape the core as easily. This forces the thermal energy to propel the core in a spiraling ball, thus creating the dynamo effect and ultimately providing us with our totally necessary magnetic field. The time you pull out a 5-cent coin, take a moment to thank the amazing properties of nickel for keeping our planet green and habitable.
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