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  • We've never been able to actually journey to the center of the Earth to see what it's like,

  • but thanks to an incredibly innovative experiment,

  • we may not have to actually go there to understand the deepest inner workings of our planet.

  • So far, we've mostly explored our planet's interior using seismic measurements

  • basically, measuring vibrations that pass through the Earth to tell us more about what's going on in there.

  • Thanks to research like this we know the Earth has an innermost, super dense solid core,

  • surrounded by a less dense, liquid outer core.

  • But an exciting new experiment tells us details about the Earth's core that we've never had access to before.

  • This research uses something called a diamond anvil cell to achieve its results.

  • As strange as it sounds, a diamond anvil cell is literally two rather glamorous looking diamonds

  • pressed together to create a tremendous amount of pressure.

  • Like, this science is truly blinged out.

  • By putting a sample of a material in a diamond anvil cell

  • we can see how it behaves under these extreme pressures.

  • Which is exactly what these researchers did with liquid iron.

  • Iron is not only the 6th most abundant element in the universe,

  • it's also thought to make up a large part of the core of our own planet,

  • and the cores of Mercury and Mars.

  • So, understanding how iron behaves under extreme circumstances is essential

  • to understanding the inner workings of our planet,

  • and even how Earth formed in the first place and how it's evolved since.

  • The tricky part though, is creating those extreme conditions for extended periods of time.

  • So far, it's been pretty tough to put liquid iron under super high pressures

  • for longer than a few microseconds

  • that's not really long enough for us to be confident about drawing hard conclusions about a material's behavior.

  • But the diamond anvil cell technique has given us just that

  • a long and extreme enough look at iron samples to tell us details we've never had before.

  • This team was able to smoosh a minuscule drop of iron down to 116 gigapascals

  • that's over a million times greater than the pressure we feel here at Earth's surface

  • and heated it with an infrared laser to 4350 Kelvin

  • that's 15-16 times hotter than average room temperature.

  • Those are temperatures and pressures really close to what you'd find at the Earth's core,

  • and they're conditions we've never reached before with diamond anvil cells.

  • They held it at those conditions long enough to use a highly focused X-ray source

  • to essentially 'take a picture' of what was going on inside that droplet of liquid iron.

  • These conditions replicate what we think iron would be experiencing in Earth's outer core.

  • So, this experiment allowed us to probe what the composition of that liquid iron core might be like.

  • But when the researchers compared the measurements they took of this drop of pure liquid iron

  • at these conditions and compared it to the seismic data we actually have of Earth's core...

  • they didn't match up.

  • The experimental iron droplet was about 8% more dense than the measurements we currently have

  • for the Earth's core, meaning that there are probably other,

  • lighter elements hanging out in Earth's core that we currently haven't identified.

  • I had no idea that so much was unknown about what's going on inside our planet, that is just totally wild to me.

  • Now, while I was able to tell you the set up and process for this experiment in pretty much less than 30 seconds,

  • it took this team over two decades to perfect this experimental set up

  • and get it to the place where it could give us these results.

  • Talk about pressure in more ways than one, man.

  • In fact, teams all over the world have been developing diamond anvil cell experiments

  • to give us more answers about our planet,

  • like one from 2019 that explored iron alloys under pressure

  • to better understand the behavior of the Earth's magnetic field.

  • But now that this latest research has successfully achieved these record-breaking

  • extreme conditions with iron,

  • they and others around the world could adapt this technique to explore other materials in the same way.

  • This could help us get a better picture of the way Earth's interior has evolved

  • and may continue to evolve over time.

  • And maybe further work like this will finally help us nail down what those still-unidentified mystery materials

  • inside the Earth really are.

  • If you want more on the cool and surprising stuff happening below the Earth's crust,

  • check out this video here, and keep coming back to Seeker for all your wave-making news.

  • If you have other high-pressure experiments you want us to cover, leave it for us in the comments down below,

  • and as always, thanks so much for watching.

  • I'll see ya next time.

We've never been able to actually journey to the center of the Earth to see what it's like,


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B1 中級

鑽石可以解開地球核心的奧祕。 (Diamonds Could Unlock the Mysteries of Earth’s Core)

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    Summer 發佈於 2021 年 01 月 14 日