Scientists recently discovered a river of molten iron, coursing at astounding speeds underneath Canada, Alaska and Russia. What is more surprising is how long the river went completely unnoticed. By studying Earth’s magnetic field, geologists were able to detect this phenomenon and assess what it means for the entire planet. A River of Molten Iron The earth is divided into layers. There’s the crust, where we live; the mantle, the outer core, and the inner core. The “river” of iron exists in the outer core, some 3,000 kilometers beneath the earth’s surface and acts similarly to jet streams in the ocean. And if calculations are correct, the river is growing and spreading, lengthening by almost 45 km every day. Life in the Outer Core Earth’s outer core is made entirely of molten metal, most of which is iron. This liquid metal is able to move underneath the surface, like the whites in an uncracked egg. Most of the planet’s magnetic field is generated from this liquid, ferromagnetic iron. It was this magnetic field that first alerted scientists to the presence of the molten river. The questions scientists want to answer are what propels this molten river and what does it mean for Earth’s magnetic field? Swept Away in the Current Rivers of water are propelled by gravity, but the molten iron requires a much larger engine. As scientists began probing the magnetic field of the river, they noticed two areas with different readings. These “strong lobes of magnetic flux” are the engine room of the molten river and are strongest where the outer core meets the mantle layer. Because they are stationary points, researchers can measure the change in the river’s magnetic fields. It’s like determining the strength of waves by watching a buoy. Scientists can then use this data to find patterns or anomalies within the Earth’s magnetic field. The Big Picture This river of molten iron deep below the surface of the Earth may not seem very relevant to everyday life, but that’s not true. In reality, a molten river that is so fast, powerful, and big and has demonstrably affected the Earth’s magnetic field might have serious implications for our planet’s well being. For instance, let’s review what Earth’s magnetic field does in the first place. Its main purpose is to deflect harmful radiation from the sun. Without a strong magnetic field, Earth would look like Mercury—no atmosphere, no water, no life. As the molten river continues to grow, its effect on the magnetic field potentially strengthens. Furthermore, if the molten river were to slow down or somehow reverse directions, what could this do to the magnetic field? Another question scientists want to answer is if there is a counterpart in the southern hemisphere. However, there are no apparent magnetic lobes to measure magnetism. Whatever happens with our new favorite river, we’ll make sure to keep you updated. Make sure to regularly check back on our blog to stay in the loop.