We humans like to think that we know about and can control everything that happens on our planet. And how’s that working for us? Yeah, control over the elements is far from the truth. Because right now, somewhere above our heads, in addition to Climate Change, the Earth's magnetic field keeps weakening at an alarming speed. And the region that concerns scientists more than any other is called the South Atlantic Anomaly. But let's start from the very beginning. In 1958, American student James Van Allen discovered that there were two radiation belts circling our planet. These belts appeared when radioactive particles from the Sun, as well as cosmic rays, got trapped in the magnetic field of our planet. This means that the belts, powered by the magnetic field (aka the magnetosphere, ooh), protect the Earth from destruction. But more about that later. For now, the main character of our story is the Earth's magnetic field itself. And it's having big problems now. The truth is that our planet's magnetic field has been weakening, and this process started more than 1,000 years ago. The situation is so serious that scientists don't deny that one day, the Earth's magnetic poles might simply flip, with North becoming South and vice versa. Although it may sound scary and confusing, this phenomenon has been happening throughout the history of our planet. The last time it occurred was approximately 780,000 years ago. Experts are still not sure if such a flip is imminent this time because it’s not an instant change. Nope, it's a long process that might suddenly reverse, like it happened 40,000 years ago when Earth was close to renaming its North Pole to the South one. Nowadays, the region that worries scientists the most is the South Atlantic Anomaly - a vast region stretching from Zimbabwe to Chile. The magnetic field in this area is so weak that it's dangerous for satellites to enter it. As you remember, the magnetosphere protects Earth from radiation. Thus, a weak magnetic field means additional hazardous radiation, which, in turn, can lead to disruption in satellites' electronics. In fact, in recent decades, the South Atlantic Anomaly has already caused several computer crashes on shuttles, and even the International Space Station. That's why, when the latter passes through the anomaly, it needs extra shielding. What's more, after the Hubble Space Telescope enters this anomalous zone, it stops taking observations and doesn't resume its work until it leaves the region. The Space-X CRS-1 Dragon spacecraft almost went out of control in October 2012. Attached to the International Space Station, it had serious problems while passing through the magnetic anomaly, but luckily, those issues were short-lived. But the next spacecraft wasn’t that fortunate. In 2016, Japan's Hitomi X-ray observatory, which was the most powerful cutting-edge satellite, was traveling through the region. Its aim was to study supernovas and black holes. But the South Atlantic Anomaly disrupted its direction-finding mechanisms and, as a result, the satellite had to rely only on gyroscopes to find its way. Unfortunately, they weren't working properly, and the observatory spun itself apart. The truth is that people have known about the changes in the magnetosphere for quite some time. But no one was sure if it was an anomaly, or a perfectly usual pattern that had existed for millions of years. Well, it turned out that people did have reason to worry. Recently, scientists have found a way to study the changes in the magnetosphere of our planet, and the results are more than alarming. But let me tell you about the Bantu people first. It was a tribe of ancient Africans who lived in the region of the Limpopo River Valley. Nowadays, this area borders with Botswana, Zimbabwe, and South Africa, and is located inside the South Atlantic Anomaly. About 1,000 years ago, during droughts, the Bantu people conducted an intriguing ritual: they burned their own clay huts, hoping that rain would come after such sacrifice. But when the clay burned at very high temperatures, it stabilized the magnetic minerals in it. That's why, when the substance cooled down, these minerals hardened according to the planet's magnetic field pattern. No wonder modern scientists were ecstatic about the discovery, since it allowed them to learn more about the magnetic field anomaly and its behavior. And guess what? They found out that the process of the weakening of the magnetosphere started long ago! The clay patterns even specified the definite periods: 400-450 CE, 700-750 CE, and 1225-1550 CE. Uh-oh, it's getting closer and closer to our time! To make a long story shorter, it appears as if something hidden deep under Africa is affecting the magnetic field of the whole planet! And scientists may have finally figured out what it could be. At least, the current weakening of the Earth's magnetosphere (which started around 160 years ago) seems to be connected to a huge reservoir of super dense rock that sits a whopping 1,800 miles under the continent. Some experts claim that the thing might be tens of millions of years old and thousands of miles wide. But how can some rock interfere with the magnetic field of the entire planet? The thing is that this rock is located right between the boiling outer core of our planet, which consists of liquid iron and nickel, and the Earth's mantle, which is much stiffer and cooler. As a result, this monster of a boulder may be disturbing the layer of iron, which is the very force that helps to create the planet's magnetic field. And even though the pole reversal I've told you about could start anywhere in the Earth's core, places like the South Atlantic Anomaly are the most likely sources of the dramatic changes. Some people believe that when south turns north, our planet will suffer a lot of catastrophic events. They say the continents will start to lurch in different directions, and it’ll trigger ruinous earthquakes, the extinction of species, and climate changes. Hmm! However, there's no proof that the consequences of the pole reversal are going to be that disastrous. Plus, scientists are still not sure whether the pole reversal will happen at all, since the events of the most recent 160 years can be just a part of a bigger-scale pattern. But let's imagine the worst-case scenario: you know, just for ---fun? What if Earth lost its magnetic field altogether, what would happen then? First, all compasses would go awry and start doing weird things. The reason for that is the nature of these devices, which are nothing more than tiny magnets. And like any magnet, they use Earth's magnetic fields to align themselves. With our planet's magnetic field gone, compasses wouldn't align north-to-south anymore. Even a small piece of magnetic rock would be able to make your compass show the wrong direction or start to "wander." Without magnetic fields, birds would stop their seasonal migrations. They use Earth's magnetic field for navigation, just like many other creatures like sea turtles, honeybees, lobsters, (ooh lobsters!) and some species of fish. So, let's say the magnetic field disappeared: in this case, migrating birds wouldn't know where to fly, and they might not survive the winter. On top of that, without Earth's magnetic field, you might never again see auroras or, as they’re also called, Northern and Southern lights. The upper atmosphere of our planet would be exposed to powerful solar winds, and the breathtaking phenomenon wouldn't be as bright as it is now. But those wouldn't be the worst consequences of the disappearance of Earth's magnetic field. No no no. The truth is that without it, we might not survive at all! Our magnetic field protects the planet from being bombarded by streams of deadly radioactive particles. If they reached the Earth's surface, people would be in real danger. See for yourself: astronauts on lunar missions told about flashes of lights they saw when they closed their eyes. It happened after cosmic rays had been passing through their retinas for some time, and later, it led to cataracts. So, if the magnetic field disappears, cosmic rays would bombard our bodies, causing serious diseases, such as cancer, and even changing our DNA! Along with health issues, technology would suffer as well. Initially, people would lose control over satellites, which would get damaged by solar storms. Without the magnetosphere, power grids, computers, and other electronics wouldn't be protected, even from the weakest of solar storms. And it just gets better…. The outcome of losing the magnetic field would be the disappearance of the air we breathe - and the solar wind would be the one to blame. This wind is so powerful that it would easily rip the planet's atmosphere off its gases. As a result, all the water on Earth would evaporate, leaving the planet bare and lifeless. Thankfully, even if it were to happen, it would be a long time from now. And scientists are launching more satellites soon to further understand the Earth’s magnetic field. Now it’s your turn: Do you think our planet will eventually lose its attraction – I mean it’s magnetic field? Or perhaps people will manage to solve this issue with the help of the newest technologies? Let me know down in the comments! If you learned something new today, then share it with a friend. But – hey! – don't go flipping your poles just yet! We have Many cool posts for you.
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