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  • You're probably like billions of other people on the planet earth, happily going about your

  • daily life without a care in the world for any of the fundamental forces that make life

  • on earth possible.

  • Yet even as you watch this video, one of those forces is experiencing an unexplained anomaly

  • and unexpectedly weakening, potentially leaving the earth vulnerable to the almost complete

  • extinction of life.

  • If what scientists are watching develop in real time persists, humanity has at best years

  • left to live, and the only thing to survive us will be microbial life in the deepest caves

  • or darkest depths.

  • In 1958 it was well understood that the sun sent a steady stream of very dangerous high

  • energy particles and radiation crashing towards the earth.

  • What kept life safe from this peril was the earth's powerful magnetic field, stretching

  • out thousands of miles into space and shielding us from the worst of the solar wind.

  • So try and imagine their horror when scientists in 1958 discovered that this invisible shield

  • we rely on for life to continue on earth, was actually weakening.

  • Known as the South Atlantic Anomaly, it is an area of weakening magnetic field that grows

  • on average by 12.4 miles per year (20 km).

  • The area has been closely monitored since its discovery, and today this chink in the

  • earth's protective armor comes down to just over 100 miles over the surface of our planet.

  • The anomaly has already taken a devastating toll on manned and unmanned spacecraft, and

  • modern satellites can't operate in the area without special precautions- or risk destruction.

  • But what is this anomaly exactly, and why is it so dangerous?

  • Texans might not like it, but the truth is all life on earth is solar powered- yes, even

  • you.

  • The food you eat either ate food that got its energy from the sun, or was food that

  • got its energy from the sun.

  • For the kids in the cheap seats, we're talking about plants here.

  • The sun is basically the giver of all life, but it can also be the taker of that same

  • life.

  • That's because all that nice warm sunshine you enjoy on a sunny summer day is only a

  • tiny percentage of the energy the sun is blasting out into space in your direction.

  • Basically, the sun is blasting a pure murder-hate beam of radiation straight at your dumb face,

  • but good guy earth is there to shield you from the worst of it so all you feel is a

  • nice warm ray of light and maybe some slight sunburn.

  • That's thanks to the earth's magnetic field, which is generated by the movement of molten

  • iron and nickel in the earth's core.

  • All that moving and shaking of those metals in our molten core generates a massive electrical

  • current, which in turn creates a magnetic field which stretches out deep into space.

  • That magnetic field is in effect a shield, which deflects or traps harmful solar wind

  • and ensures that instead of your DNA being blasted apart, you'll at worst suffer a sunburn

  • from staying outside too long.

  • But just how bad could it really be if the magnetic field were to collapse suddenly?

  • That's a great question, and we're glad you asked.

  • Four and a half billion years ago Mars had a thick, luscious atmosphere, and plenty of

  • liquid water to go around.

  • We can see evidence of huge lakes and rivers all over the surface of the planet, and we

  • know from studying the chemistry of the planet that it was once wrapped up in a thick atmosphere.

  • Then, everything changed- in geological time scales, practically overnight.

  • The world that may have once held an advanced dolphin species capable of space flight- you

  • can't prove that didn't exist- is today only a dusty rock.

  • The killer?

  • Its magnetic field.

  • Scientists still don't understand why Mars' magnetic field shut down, but they believe

  • that it was due to its smaller size compared to earth, as well as the composition of its

  • core.

  • The earth is bigger than Mars- almost twice as big- which means we have a large molten

  • core that would take longer to cool than Mars' own core.

  • But that might only be part of the picture.

  • Rock is a great insulator, that's why our core has remained molten so long- but it's

  • not just heat from its original formation that's still keeping the core hot, but also

  • the decay of radioactive elements inside our core that's helping to keep things nice and

  • warm.

  • Some scientists suspect that Mars lacked such heavy radioactive elements in its core, which

  • would have led to a much faster cooling core than the Earth's own.

  • With a weakening magnetic field, the solar wind sandblasted Mars' atmosphere away, and

  • eventually, its water.

  • Any life- such as space-faring dolphins- would have been bombarded by cosmic and solar radiation,

  • their DNA destroyed by high energy particles ripping it to pieces.

  • Unless that life moved deep underground, extinction was quick to follow.

  • And now, it may happen here on Earth.

  • The South Atlantic Anomaly has been closely monitored for decades, and has now split into

  • two 'valleys' that continue to move across the ocean and grow in size.

  • However, it's not quite all doom and gloom just yet, as new data shows that the anomaly

  • may perhaps be part of a natural cycle that's been going on for millions of years.

  • We already know to expect anomalies in the Earth's magnetic field, and that's because

  • the molten core is not uniform in its iron and nickel content- who's motion generates

  • the magnetic field.

  • These irregularities in content will inevitably lead to irregularities in the strength of

  • the magnetic field around the earth, and thus the Southern Atlantic Anomaly is born.

  • There's no evidence that the earth's magnetic field ever weakened to the point of causing

  • a mass extinction event, so scientists are hopeful that the SAA will continue to evolve

  • over time before eventually correcting itself.

  • For now the greatest danger that the SAA poses is to low earth satellites, which frequently

  • pass through the anomaly.

  • They must be careful to shut down sensitive electronics or suffer serious consequences-

  • such as a Japanese satellite that destroyed itself when charged particles slipping through

  • the weakened magnetic field damaged some of its electronics.

  • Even the space shuttle experienced the shutting down of laptops as it flew through the anomaly,

  • and the ISS regularly passes through it but thanks to its thick shielding suffers few

  • if any ill effects.

  • While scientists don't expect the SAA to lead to a magnetic field collapse, there may be

  • no telling how the Southern Atlantic Anomaly evolves in the future.

  • If things take a turn for the worse and the anomaly dips below the atmosphere- something

  • it is already dangerously close to doing- it could spell disaster for any living beings

  • in the geographic vicinity of the anomaly.

  • Thankfully for now the anomaly is over the Southern Atlantic, but as it moves and grows

  • it could eventually pass over heavy population centers.

  • What the Southern Atlantic Anomaly means for life on earth is still largely unknown.

  • Before we're all disintegrated by an angry sun, go watch Worst Natural Disasters In Human

  • History, or click this other video instead!

You're probably like billions of other people on the planet earth, happily going about your

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Scientists Discover Mysterious Anomaly That Could Destroy The Planet

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    Summer posted on 2021/04/13
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