Earth’s north magnetic pole is on the move – here’s what will happen when our poles flip

Following is a transcript of the video.

Narrator: Did you know that Earth has two North Poles? There’s the geographic North Pole, which never changes. And there’s the magnetic North Pole, which is always on the move. And right now it’s moving faster than usual.

Over the past 150 years, the magnetic North Pole has casually wandered 685 miles across northern Canada. But right now it’s racing 25 miles a year to the northwest.

This could be a sign that we’re about to experience something humans have never seen before: a magnetic polar flip. And when this happens, it could affect much more than just your compass.

Alanna Mitchell: Right now on the surface of the planet, it looks like it’s just a bar magnet. Our compasses are just pointing to one pole at a time because there’s a dominant two-pole system.

But sometimes, Earth doesn’t always just have a single magnetic North and South Pole. Evidence suggests that, for hundreds to thousands of years at a time, our planet has had four, six, and even eight poles at a time. This is what has happened when the magnetic poles flipped in the past. And when it happens again, it won’t be good news for humans.

Now you might think, eight poles must be better than two. But the reality is that: Multiple magnetic fields would fight each other. This could weaken Earth’s protective magnetic field by up to 90% during a polar flip.

Earth’s magnetic field is what shields us from harmful space radiation which can damage cells, cause cancer, and fry electronic circuits and electrical grids. With a weaker field in place, some scientists think this could expose planes to higher levels of radiation, making flights less safe.

This could also disrupt the internal compass in many animals who use the magnetic field for navigation. Even more extreme, it could make certain places on the planet too dangerous to live. But what exactly will take place on the surface is less clear than what will undoubtedly happen in space.

Satellites and crewed space missions will need extra shielding that we’ll have to provide ourselves. Without it, intense cosmic and solar radiation will fry circuit boards and increase the risk of cancer in astronauts.

Our modern way of life could cease to exist. We know this because we’re already seeing a glimpse of this in an area called the South Atlantic Anomaly. Turns out, the direction of a portion of the magnetic field deep beneath this area has already flipped! And scientists say that’s one reason why the field has been steadily weakening since 1840.

As a result, the Hubble Space Telescope and other satellites often shut down their sensitive electronics as they pass over the area. And astronauts on the International Space Station reported seeing a higher number of bright flashes of light in their vision, thought to be caused by high-energy cosmic rays that the weaker field can’t hold back.

Since experts started measuring the Anomaly a few decades ago, it has grown in size and now covers a fifth (20.3%) of Earth’s surface, with no signs of shrinking anytime soon. This is so extreme that it could be a sign we’re on the brink of a polar flip, or we may already be in the midst of one!

But scientists remain skeptical, mainly because …

Mitchell: They don’t know. The last time the poles reversed was 780,000 years ago so it’s not like we have a record for this.

Turns out 780,000 years is over double the time Earth usually takes between flips.

Mitchell: In the past 65 million years since the last mass extinction there have been reversals roughly every 300,000 years.

So what gives? Well, scientists haven’t figured it out yet. It’s unnerving to think that our modern way of life – banking, the stock exchange, missile tracking, GPS – relies on the outcome of something we can neither predict, nor control. One study went so far as to estimate that a single, giant solar storm today could cost the US up to $41.5 billion a day in damages.

And that’s with Earth’s magnetic field at its current strength. It’s frightening to imagine the devastation a storm would bring to an Earth with a magnetic field only 10% as strong.

We may not be able to stop a polar flip, but we can at least start to take measures to minimize the damage. The first step? Figure out what’s going on with this whacky field.

On the hunt are the European Space Agency’s SWARM satellites, which are collecting the most precise data on the strength of Earth’s magnetic field. Right now, they could be our greatest hope for solving this riddle.

EDITOR’S NOTE: This video was originally published on April 9, 2018.

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What would happen if humans tried to land on Jupiter

  • Jupiter is made of mostly hydrogen and helium gas.
  • If you tried to land on Jupiter, it would be a bad idea.
  • You’d face extremely hot temperatures and you’d free-float in mid-Jupiter with no way of escaping.
  • Visit Business Insider’s homepage for more stories.

Following is a transcript of the video.

Narrator: The best way to explore a new world is to land on it. That’s why humans have sent spacecraft to the Moon, Venus, Mars, Saturn’s moon, Titan, and more.

But there are a few places in the solar system we will never understand as well as we’d like. One of them is Jupiter.

Jupiter is made of mostly hydrogen and helium gas. So, trying to land on it would be like trying to land on a cloud here on Earth. There’s no outer crust to break your fall on Jupiter. Just an endless stretch of atmosphere.

The big question, then, is: Could you fall through one end of Jupiter and out the other? It turns out, you wouldn’t even make it halfway. Here’s what would happen if you tried to land on Jupiter.

*It’s important to note that we feature the Lunar Lander for the first half of the descent. In reality, the Lunar Lander is relatively delicate compared to, say, NASA’s Orion spacecraft. Therefore, the Lunar Lander would not be used for a mission to land on any world that contains an atmosphere, including Jupiter. However, any spacecraft, no matter how robust, would not survive for long in Jupiter, so the Lunar Lander is as good of a choice as any for this hypothetical scenario. 

First things first, Jupiter’s atmosphere has no oxygen. So make sure you bring plenty with you to breathe. The next problem is the scorching temperatures. So pack an air conditioner. Now, you’re ready for a journey of epic proportions.

For scale, here’s how many Earths you could stack from Jupiter’s center. As you enter the top of the atmosphere, you’re be traveling at 110,000 mph under the pull of Jupiter’s gravity.

But brace yourself. You’ll quickly hit the denser atmosphere below, which will hit you like a wall. It won’t be enough to stop you, though.

After about 3 minutes you’ll reach the cloud tops 155 miles down. Here, you’ll experience the full brunt of Jupiter’s rotation. Jupiter is the fastest rotating planet in our solar system. One day lasts about 9.5 Earth hours. This creates powerful winds that can whip around the planet at more than 300 mph.

About 75 miles below the clouds, you reach the limit of human exploration. The Galileo probe made it this far when it dove into Jupiter’s atmosphere in 1995. It only lasted 58 minutes before losing contact and was eventually destroyed by the crushing pressures.

Down here, the pressure is nearly 100 times what it is at Earth’s surface.  And you won’t be able to see anything, so you’ll have to rely on instruments to explore your surroundings.

By 430 miles down, the pressure is 1,150 times higher. You might survive down here if you were in a spacecraft built like the Trieste submarine – the deepest diving submarine on Earth. Any deeper and the pressure and temperature will be too great for a spacecraft to endure.

However, let’s say you could find a way to descend even farther. You will uncover some of Jupiter’s grandest mysteries. But, sadly, you’ll have no way to tell anyone. Jupiter’s deep atmosphere absorbs radio waves, so you’ll be shut off from the outside world- unable to communicate.

Once you’ve reached 2,500 miles down, the temperature is 6,100 ºF.  That’s hot enough to melt tungsten, the metal with the highest melting point in the Universe. At this point, you will have been falling for at least 12 hours. And you won’t even be halfway through.

At 13,000 miles down, you reach Jupiter’s innermost layer. Here the pressure is 2 million times stronger than at Earth’s surface. And the temperature is hotter than the surface of the sun. These conditions are so extreme they change the chemistry of the hydrogen around you. Hydrogen molecules are forced so close together that their electrons break lose, forming an unusual substance called metallic hydrogen. Metallic hydrogen is highly reflective. So, if you tried using lights to see down here it would be impossible.

And it’s as dense as a rock. So, as you travel deeper, the buoyancy force from the metallic hydrogen counteracts gravity’s downward pull.  Eventually, that buoyancy will shoot you back up until gravity pulls you back down, sort of like a yo-yo. And when those two forces equal, you’ll be left free-floating in mid-Jupiter, unable to move up or down, and no way to escape!

Suffice it say, trying to land on Jupiter is a bad idea. We may never see what’s beneath those majestic clouds. But we can still study and admire this mysterious planet from afar.

 

A special thanks to Kunio Sayanagi at Hampton University, for his help with this video.

EDITOR’S NOTE: This video was originally published in February 2018.

Read the original article on Business Insider