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At the equator, the Earth rotates at a speed of about 1,600 kilometers per hour. But what if it suddenly stopped?
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You and everything else could be flying at hundreds of miles per hour unless you are at the poles.
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The Earth's rotation is actually slowing down at an estimated rate of 2.3 milliseconds per century.
"Stop the world, I want out." This irritated expression has been around since the 1950s and is used in both classical and modern music.
But if the world really stopped turning, the consequences would belong less in a romantic musical and more in an apocalyptic horror film.
What if the Earth suddenly stopped?
Imagine walking on a sunny beach somewhere along the equator. The Earth below you is spinning eastward at a speed of 1,040 miles per hour (1,674 kilometers per hour).
But because you, the sand, and everything else around you are moving at the same speed, your walk will feel slow and relaxing.
Then the world stops beneath you and you get out. On the contrary, you are thrown away.
Thanks to Newton's first law from inertia you initially fly eastwards at a speed of about 1,600 kilometers per hour. Wherever you land, whether in the ocean or on the ground, the force of the impact would probably kill you.
"Water would also feel this sudden acceleration," says Joseph Levy, associate professor of earth and environmental geosciences at Colgate University. So you'll probably see the ocean sloshing around quite a bit before impact.
Trees and buildings would also not be safe, even though they are rooted in the ground. "Earth materials are strong under pressure, but very weak under tension," Levy said.
In other words, that nearby brick building can house hundreds of people because the floors and support beams compact under their weight.
But the inertia pushing the building eastward from Earth's sudden stop would be much stronger than the mortar holding the bricks together, so the entire structure could tear apart, Levy said.
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If that makes you feel better, your hypothetical cousin in Antarctica would probably survive with a few bruises. "Near the poles, the axis of rotation is much smaller, so the rotation speed is much smaller," Levy said.
But you have to be very close - within 89.9 degrees north latitude, Levy said, or about seven miles from the poles. At that distance you would probably just stumble forward at a walking pace.
But your friends in Denmark or Australia probably wouldn't make it. Most places where humans live are far enough from the poles that their residents would still fly to hundreds of kilometers per hour.
What if the Earth gradually stopped spinning?
"In natural systems, nothing ever really comes to a complete stop," Levy said.
So what if the Earth slows down over days or weeks?
A gradual deceleration might keep you from getting airborne, but once the deceleration stopped you would still have a lot of problems.
"Over the course of the year, as the Earth revolved around the sun, half of the planet would be at night and the other half in full light, but half would be constantly changing over the course of the year," said Levy.
Instead of twelve hours, a 'day' could last six months. The nonstop sun would roast nearby crops and evaporate much of the water on your half of the world, Levy added.
The next six-month night probably wouldn't be much better. A lack of light and heat would likely kill many remaining plants and freeze water in ice sheets.
Higher latitudes could be safer because sunlight wouldn't be too intense near the poles, Levy said. But you would have to get used to a nomadic lifestyle, forever chasing daylight around the world.
You may also have to deal with unexpected weather.
On a rotating Earth, most of the solar radiation strikes the planet's equator. "Broadly speaking, warm air rises over the equator and falls over the poles after it cools," Levy said. Ocean currents follow a similar up-down cycle.
But when only half the planet receives intense sunlight for months, the planet experiences a second, sideways temperature gradient, making predicting the weather twice as complicated.
"Winds would blow over the terminator - the shadow line - and bring cold air back from the night side, where it would warm and rise on the day side," Levy added.
Could the world ever really stop turning?
Don't panic, but the Earth's rotation is slowing down thanks to a process called tidal braking.
Our moon's gravity causes an infinitesimal drag on our planet's rotation, so every century Earth's rotation slows down an additional 2.3 milliseconds according to NASA.
But it's unlikely the moon will ever completely block Earth. "The Earth is much larger than the moon and therefore has much greater angular momentum," says Levy.
One way to significantly slow the Earth's rotation would be for humanity to treat it as a giant energy source. For example, we could theoretically consider the Earth as one flywheel system storing the kinetic energy of its rotation to meet our energy needs.
"If you used the planet's spinning momentum to meet all human energy needs, it would still take about 1 million years to bring the planet to a standstill," Levy said.
It is virtually impossible that any object in space could stop the Earth's rotation before then. "The Earth's angular momentum is too great to slow anything other than a complete catastrophe," Levy said.
So the world won't stop anytime soon when you get out - and that's probably a good thing.
Read the original article on Business Insider