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We've never been able to actually journey to the center of the Earth to see what it's like,
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but thanks to an incredibly innovative experiment,
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we may not have to actually go there to understand the deepest inner workings of our planet.
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So far, we've mostly explored our planet's interior using seismic measurements—
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basically, measuring vibrations that pass through the Earth to tell us more about what's going on in there.
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Thanks to research like this we know the Earth has an innermost, super dense solid core,
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surrounded by a less dense, liquid outer core.
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But an exciting new experiment tells us details about the Earth's core that we've never had access to before.
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This research uses something called a diamond anvil cell to achieve its results.
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As strange as it sounds, a diamond anvil cell is literally two rather glamorous looking diamonds
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pressed together to create a tremendous amount of pressure.
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Like, this science is truly blinged out.
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By putting a sample of a material in a diamond anvil cell
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we can see how it behaves under these extreme pressures.
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Which is exactly what these researchers did with liquid iron.
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Iron is not only the 6th most abundant element in the universe,
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it's also thought to make up a large part of the core of our own planet,
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and the cores of Mercury and Mars.
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So, understanding how iron behaves under extreme circumstances is essential
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to understanding the inner workings of our planet,
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and even how Earth formed in the first place and how it's evolved since.
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The tricky part though, is creating those extreme conditions for extended periods of time.
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So far, it's been pretty tough to put liquid iron under super high pressures
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for longer than a few microseconds—
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that's not really long enough for us to be confident about drawing hard conclusions about a material's behavior.
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But the diamond anvil cell technique has given us just that—
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a long and extreme enough look at iron samples to tell us details we've never had before.
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This team was able to smoosh a minuscule drop of iron down to 116 gigapascals—
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that's over a million times greater than the pressure we feel here at Earth's surface—
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and heated it with an infrared laser to 4350 Kelvin—
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that's 15-16 times hotter than average room temperature.
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Those are temperatures and pressures really close to what you'd find at the Earth's core,
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and they're conditions we've never reached before with diamond anvil cells.
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They held it at those conditions long enough to use a highly focused X-ray source
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to essentially 'take a picture' of what was going on inside that droplet of liquid iron.
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These conditions replicate what we think iron would be experiencing in Earth's outer core.
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So, this experiment allowed us to probe what the composition of that liquid iron core might be like.
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But when the researchers compared the measurements they took of this drop of pure liquid iron
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at these conditions and compared it to the seismic data we actually have of Earth's core...
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they didn't match up.
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The experimental iron droplet was about 8% more dense than the measurements we currently have
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for the Earth's core, meaning that there are probably other,
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lighter elements hanging out in Earth's core that we currently haven't identified.
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I had no idea that so much was unknown about what's going on inside our planet, that is just totally wild to me.
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Now, while I was able to tell you the set up and process for this experiment in pretty much less than 30 seconds,
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it took this team over two decades to perfect this experimental set up
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and get it to the place where it could give us these results.
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Talk about pressure in more ways than one, man.
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In fact, teams all over the world have been developing diamond anvil cell experiments
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to give us more answers about our planet,
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like one from 2019 that explored iron alloys under pressure
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to better understand the behavior of the Earth's magnetic field.
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But now that this latest research has successfully achieved these record-breaking
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extreme conditions with iron,
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they and others around the world could adapt this technique to explore other materials in the same way.
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This could help us get a better picture of the way Earth's interior has evolved
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and may continue to evolve over time.
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And maybe further work like this will finally help us nail down what those still-unidentified mystery materials
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inside the Earth really are.
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If you want more on the cool and surprising stuff happening below the Earth's crust,
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check out this video here, and keep coming back to Seeker for all your wave-making news.
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If you have other high-pressure experiments you want us to cover, leave it for us in the comments down below,
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and as always, thanks so much for watching.
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I'll see ya next time.