Blissed Out On Earth’s Blingy Core

6:48 minutes

A year ago, astronomers discovered diamond rain on Uranus and Neptune. Now, scientists believe that up to two percent of the Earth is made up of those very same gemstones. Models show that sound waves seem to travel too quickly through parts of earth’s core, which extend into the mantle around 120 to 150 kilometers deep. It’s just a theory, scientists say. One way to explain this would be the presence of diamonds.

[Happiness: It’s complicated.]

Ryan Mandelbaum, science writer for Gizmodo, joins Ira to explain why scientists are blissed out on the idea of Earth’s blingy core. Plus, somewhere in the nearby solar system, a planet is getting swallowed by it’s sun.

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Segment Guests

Ryan Mandelbaum

Ryan Mandelbaum is a science writer and birder based in Brooklyn, New York.

Segment Transcript

IRA FLATOW: This is Science Friday. I’m Ira Flatow. First, it was diamond rain on Uranus and Neptune, and now scientists believe that our very own planet may be full of the very same gemstone. And it’s just a hunch, but they suspect that as much as 2% of the Earth is made up of diamonds. So what makes them suspect our planet’s chock full of the sparkly stuff? Well, here to tell us that story, as well as other short subjects in science, is Ryan Mandelbaum, science writer for Gizmodo. Always good to see you, Ryan.

RYAN MANDELBAUM: Yeah, always great seeing you, Ira. How’s everything going?

IRA FLATOW: Hi. So you know that song, the Earth moves under my feet? Well there are diamonds under my feet?

RYAN MANDELBAUM: Maybe. So what happened was, there’s these cores of continents called cratons. You know, the oldest part of our continents, and sound waves move too quickly through them, and some scientists did some calculating, some lab experiments, and figured out that if the Earth was both 50% of one kind of rock, and then 2% diamonds, it would explain the sound waves moving too fast. So it’s a hypothesis is what I’m going to say. But it would be crazy, of course.

IRA FLATOW: Do we know where they might be, so we can start looking for them?

RYAN MANDELBAUM: They would be like 100 miles underground.


RYAN MANDELBAUM: And so I mean, the issue is that when the diamond ore comes to the surface of the Earth, it doesn’t contain 2% diamonds. So the question is, OK, well, if they’re there, where are the diamonds. So you know, like I said, hypothesis, but people are looking, and maybe.

IRA FLATOW: Is there any way to follow up this with an experiment of something?

RYAN MANDELBAUM: Well, unless you like, recreate the movie, The Core, it’s going to be pretty hard. But I mean, there’s just more modeling and more observations to be done. I mean, with more science, hopefully, they’ll be able to find something out.

IRA FLATOW: Would these be the same kinds of diamonds I’m getting at the jewelry store?

RYAN MANDELBAUM: They wouldn’t be quite as pretty. They wouldn’t be cut diamonds.

IRA FLATOW: No. But I guess diamonds are carbon, right, so diamonds–

RYAN MANDELBAUM: Still carbon. And it would be crazy for the Earth to have that much carbon underneath the mantle like that. I mean, it would be important.

IRA FLATOW: Listen to this segue I’m going to do. Dark black diamond– well, you know, carbon. There’s this story you have about the black sarcophagus in Egypt. You really love this one, I know.

RYAN MANDELBAUM: If you are on Twitter today, you should look at the jokes that people are making. What happened was, on July 1st in Egypt, there was a sarcophagus found, a 2000-year-old sarcophagus in Alexandria, Egypt. And everybody thought this black granite thing, you know, maybe it’s cursed. Like, should we open this sarcophagus lest we unleash some crazy thing? But they opened it up yesterday, and it was not nearly as exciting. It was three skeletons in a pool of red sewage.

IRA FLATOW: Highly disappointing, I imagine.

RYAN MANDELBAUM: Disappointing, but still scientifically interesting. I mean, these skeletons are, again, 2000 years old inside this sarcophagus. It’s just that, you know, the mummies weren’t as well preserved as you might have hoped. But now people are joking online that the water must be cursed or something, so you know, let us drink the red juice.

IRA FLATOW: The biggest nonevent since Geraldo Rivera’s Al Capone vault opening back in the 80s.

RYAN MANDELBAUM: At least there was something in the sarcophagus.

IRA FLATOW: There was something in there. All right, let’s go out to, speaking of strange, a strange physics story. I know you’re really good at finding these, so tell us about these two particles spinning very, very fast.

RYAN MANDELBAUM: Yeah, so scientists constructed these nanoparticles made of silica, and so they’re about 100 nanometers, like the size of viruses. And they spin a billion times per second, which is the fastest mechanical motion on record. So that is cool on its own. And the way they make it spin is by shining it with light that has been circularly polarized, so the electric field is spinning.

IRA FLATOW: And why do they do this?

RYAN MANDELBAUM: Well, they did it for several reasons. One of them was looking to create a torsion balance with a different experiment, which is sort of like a little force detector. Another was just doing it because they wanted to test the fundamental limits of physics. But really, like, you may have read in quantum mechanics this idea of sort of the quantum vacuum, that particles are appearing and disappearing out of nowhere in the vacuum of space. And if that was true, then perhaps these virtual particles would create friction against the spinning nanoparticle, and we might be able to detect this friction of spacetime itself.


RYAN MANDELBAUM: Head exploding motion.

IRA FLATOW: All right, so let me see if I understand this. So you know, let’s say it takes a certain amount of energy and you can rev up the spinning particles, theoretically to a certain speed, right. But if you apply that energy, and it doesn’t get to that speed, there’s something holding the particles back from spinning.

RYAN MANDELBAUM: That’s the idea, that perhaps they measured some friction from the vacuum fluctuations of space.

IRA FLATOW: Like trying to run in water, under water.

RYAN MANDELBAUM: Yeah. It’s like the way that you can tell that there’s air resistance, because when you do this, you know, you flap your hands back and forth, you make wind.

IRA FLATOW: Right. Wow. And so we know from quantum mechanics that particles kind of pop in and out, and this is an idea to try to prove that theory there, even though we can’t see them.

RYAN MANDELBAUM: Yup, basically. Well, yeah, actually.

IRA FLATOW: Wow, that’s kind of cool. This is a don’t try this at home sort of thing, unless you can spin it up, right.

RYAN MANDELBAUM: If you’ve got the lab equipment, it’s not going to hurt anyone.

IRA FLATOW: Let’s talk about something really amazing that astronomers saw for the first time using one of our space telescopes, a planet getting eaten by a star.

RYAN MANDELBAUM: Right. So there is, about 450 light years from Earth, so sort of in our stellar neighborhood, is this star called RW Aur A, and they observed it dimming every few decades, and the dimming would last a month, but then in 2011, the dimming behavior changed. And modeling appears to show that this could be from not just a planet being eaten by the star, but pieces of planets colliding and then being sucked up by this young star. It’s cool.

IRA FLATOW: Yeah, it’s cool.

RYAN MANDELBAUM: I mean, the idea is that this is a young star, probably only a few million years old, and we think that around these young stars are these disks of rock and debris. And in that case, then there is a lot of chaos that’s going on around these early stars. Planets begin forming out of this debris, and it’s possible that you know, some collision would have ended up in the star eating up some pieces of planets.

IRA FLATOW: So sort of seeing what might have happened in our own early days of the solar system.

RYAN MANDELBAUM: Exactly. Looking at these early, young stars could potentially shed some light on our own solar system.

IRA FLATOW: Wow. You always bring such good stuff.

RYAN MANDELBAUM: I love this stuff.

IRA FLATOW: This is great. It is good stuff. And you know, you like getting your mind blown, your hair hurt, just thinking big thoughts about physics and our kind of thing. It’s kind of cool.

RYAN MANDELBAUM: It’s just like reading the stuff I see on the internet.

IRA FLATOW: All right. Well, keep it coming and keep coming back to us, Ryan,


IRA FLATOW: Ryan Mandelbaum, science writer for Gizmodo.

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