(Roughly) Daily

“In the landscape of extinction, precision is next to godliness”*…

There is a portion of the sky where no spacefarer wants to go. It causes Astronauts to see shooting stars in front of their eyes, sets off emergency sensors and renders satellites useless. This Bermuda Triangle of space isn’t just a cause for concern for our future of space exploration, it could be the sign of something far more deadly. This may herald an event that last happened 42,000 years ago, which wiped out our closest relative, the Neanderthals. Welcome to the terrifying world of the South Atlantic Anomaly.

In the 80s engineers noticed that most satellite errors happened over South America and the South Atlantic. These errors ranged from minor glitches, wiped data to full-blown crashed satellites. But they couldn’t quite pinpoint what was causing these troubling errors, they named this mysterious area the South Atlantic Anomaly (SAA).

We didn’t understand the dangers of this region for a long time. When the Hubble Space Telescope first turned on in 1990 they found that the computers kept crashing and data was corrupted almost every time it flew over the South Atlantic. Not wanting their billion-dollar telescope to crash to Earth, the engineers had no choice but to switch it off every time it passed over this deadly patch of sky, and still do today. Not ideal, but it saves the telescope from this mysteriously dangerous part of space.

So what makes the South Atlantic Anomaly so dangerous? It turns out it is all down to the Sun and a crack in Earths armour caused some very bizarre geophysics.

So what does struggling satellites means for us here on Earth? Well, quite a lot really. It could be a sign of something much more deadly, a geomagnetic reversal.

When we picture the Earth’s magnetic field we often think of it as unchanging. It is our eternal armour from deadly solar radiation as well as the guide for our sailors. Even some birds have evolved iron-rich cells in their eyes, enabling them to ‘see’ the magnetic field and navigate the globe. But the magnetic north pole hasn’t always been in the north.

The magnetic poles have flipped repeatedly over the millennia. The field weakens, disappears and then reappears in the opposite direction. We know this because iron-rich lava aligns to the magnetic field and then sets, so we can look at ancient rocks and see what direction magnetic north was when it formed.

We don’t have a complete understanding of how the magnetic field is generated and why it flips. We know that convection currents of iron-rich mantle create the field, but the interactions between these immense systems are complex and hidden from us. What’s more, there are no patterns to the past flipping events, so it is very hard to predict when one will happen.

But, models and simulations show that when the field gets weaker at the beginning of a magnetic flip, it seems to happen in a random area and then grows from there. The poles also start to drift quite dramatically and chaotically. This is worrying because not only does the South Atlantic Anomaly look like the weakening in a simulation, it is also growing, and the North pole is drifting further each year.

… So, it seems at least plausible that the South Atlantic Anomaly is the start of the next geomagnetic flip. If so, it could have enormous consequences for us!

The last time a flip happened was 42,000 years ago, but it was only a temporary event, and the poles returned to their previous locations, this is known as the Laschamps Excursion, and it lasted for about a thousand years. That meant Earth was without its essential protective shield for an awfully long time.

Now, 42,000 years ago is a significant time. This was when Neanderthals died out. We (Homo Sapiens) also started using caves, red ochre body paint, and the global craze of cave painting started. It was also when a lot of ice-age megafauna died out. All of which has been linked to the flipping of the poles during this period. This extinction event and Sapien revolution has been called the Adams Event (after Douglas Adams and the infamous 42).  

This theory suggests that when the poles flipped, the Earth had a thousand years without its protective layer, so the planet was bombarded with radiation. This depleted ozone, increased radiation on the surface, messed with weather patterns and caused abrupt climate change.

Scientist even suggests that this is why we suddenly took to living in caves and using red ochre. We had to hide from the deadly rays of the Sun, and if we ventured out, we needed a powerful suncream, like powdered red ochre. This is why red ochre hand paintings became so widespread around this time.

But these immense changes hit one species particularly hard. Neanderthals were likely red-headed, light-skinned and mostly dwelt in steppes (grassy plains) and woodlands. They probably got sunburnt a lot. Unlike Homo Sapiens, it seems as though Neanderthals didn’t use red ochre much at all! All of this means that cancers would have been a deadly problem for them.

To make all this even worse, the radiation increased the strength of electrical storms, changed the weather patterns and screwed up many ecosystems. So the food that the Neanderthals hunted my have been driven away or gone extinct. It seems Neanderthals died out because they starved to death while being baked by the Sun. Meanwhile, we Homo Sapiens hid from the Sun, used weird sunscreen and adapted to new foods…

These flipping events take hundreds or thousands of years to pass due to the amount of heavy magma that needs to shift to cause a flip (however it is hypothesised it could take as little as a month in extreme circumstances). So we aren’t in any danger of waking up to a new direction for North. But, over the next few decades or hundreds of years, we will see the South Atlantic Anomaly grow and potentially be joined by many other areas of weak magnetism. We may even see some local flips in a few hundred years.

So, it seems at least plausible that the South Atlantic Anomaly is the start of the next geomagnetic flip. If so, it could have enormous consequences for us!

The South Atlantic Anomaly: Earth’s deadly weakness: “Do Failing Satellites Foretell An Imminent Extinction?” From Will Lockett (@welockett).

* Samuel Beckett

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As we search for true north, we might send charged birthday greetings to a man whose life work could be at risk if there’s a flip (or an intense solar storm), Elihu Thomson; he was born on this date in 1853. An engineer and inventor, he was instrumental in developing the practical applications of electricity, especially alternating current. He invented electric welding and other important advances in electric lighting and power (among his lifetime total of about 700 patents). Thomson was also a cofounder of the General Electric Company (in 1892, in a merger of his Thomson-Houston Electric Company with the Edison Company.

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