It's Raining Diamonds! Where in the world is it raining diamonds? What in the world are diamonds made of anyway? And how in the world can we forecast the "weather" on Neptune and Uranus? Join Guy Raz and Mindy Thomas for our most most sparkly episode yet! It's the latest Who, What, When, Where, Why, How, and WOW in the World of DIAMOND RAIN!
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It's Raining Diamonds!

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It's Raining Diamonds!

It's Raining Diamonds!

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  • <iframe src="" width="100%" height="290" frameborder="0" scrolling="no" title="NPR embedded audio player">
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UNIDENTIFIED MAN #1: Stay seated. Three, two, one, ignition.

UNIDENTIFIED MAN #2: Get ready for an adventure of magnificent proportion.


THE POP UPS: (Singing) I don't know what you've been told, but we're in a golden age - so many discoveries that are jumping off the page. Wow in the world. Wow in the world. Wow in the world. Wow in the world. Wow in the world. Wow in the world. Wow in the world. Wow in the world. Wow in the world.

UNIDENTIFIED MAN #3: With Guy and Mindy.

UNIDENTIFIED MAN #1: We're on our way, Houston.




Hey, Guy Raz, what are you doing in here? Guy Raz?

RAZ: Cold, thick...

THOMAS: You in the lab?

RAZ: ...Pretty slushy.

THOMAS: Whoa, did somebody inherit a gas station rest stop in here?

RAZ: Hey, Mindy (slurping).

THOMAS: Uh, Guy Raz?

RAZ: Uh, yeah, what's (slurping) going on (slurping)?

THOMAS: What's going on? Shouldn't you be the one answering that question?

RAZ: Well, I'm just, you know, running some experiments. How about you?

THOMAS: How about me? What about you, Guy Raz? This is highly unusual behavior for you. Are you sick? Here, give me your armpit. Let me feel your forehead.

RAZ: I told you I'm just making some observations, just writing some field notes down in my journal.

THOMAS: Nope, not buying it. You are standing here at this lab table with five different Slurpees, slurping them all up so loudly I thought there was an intruder in here. I almost called the police. Guy Raz, you are busted. Can I have one of those?

RAZ: Well, I'm just trying to understand space atmospherics.

THOMAS: Space atmospherics? You are drinking five Slurpees in a lab.

RAZ: Well, it's a way for me to understand Neptune and Uranus a bit better.

THOMAS: Neptune and Uranus, right. Did you forget two weeks ago when you told me to cool it on that bucket of Slurpee I was enjoying?


RAZ: Hey, Mindy, that Slurpee that you're drinking, it has way too much sugar.

THOMAS: Did you say something?

RAZ: Actually, about 21 teaspoons of sugar in that one you're drinking. And according to the World Health Organization...

THOMAS: Sorry, couldn't hear that.

RAZ: ...You really shouldn't be eating or drinking more than seven or maybe eight teaspoons of sugar a day.

THOMAS: Ah, brain freeze.


RAZ: Oh, yeah, I forgot about that. I guess you're right. I must be drinking enough sugar for the entire week right now.

THOMAS: Exacdoritos (ph). So what are these five large Slurpees doing on the lab table, Mr. Kombucha Pants?

RAZ: Well, I didn't want to mix the flavors. I mean, they were all in slightly different stages of frozenness, if you know what I mean.

THOMAS: Oh, yeah, actually, I know exactly what you mean.

RAZ: Yeah.

THOMAS: Like, when you're at the Slurpee machine and the flavor you want has that red flashing light above it. And then the Slurpee comes out more like a soda, instead of a Slurpee...

RAZ: Well...

THOMAS: ...Like a soggy, sloppy Slurpee.

RAZ: Yeah, I...

THOMAS: The worst, am I right?

RAZ: Well, you know, I really just wanted to figure out if I could, you know, taste what the atmosphere of Neptune or Uranus might feel like.

THOMAS: But they don't even have a 7-Eleven in outer space.

RAZ: Well, I didn't say this was the perfect observational experiment, but...

THOMAS: Wait a minute. I think I know exactly what you're talking about.

RAZ: What?

THOMAS: Well, Neptune and Uranus are really, really cold planets, right?

RAZ: Yeah, that's right.

THOMAS: And the reason they're so cold is because they are so, so, so far away from the sun.

RAZ: Actually, the farthest in our solar system.

THOMAS: Which means that the sun's heat doesn't even really warm them up.

RAZ: That sounds about right.

THOMAS: But I also know that Neptune and Uranus are mostly floating planets of thick gases, like hydrogen and helium and methane.

RAZ: And deep, deep, deep in the middle of those planets, Mindy, if you could travel all the way to the core, you would find a rocky little center.

THOMAS: Kind of like the opposite of a Tootsie Pop.

RAZ: But long before you got to that rocky center, or core...


RAZ: ...You'd have to go through thousands and thousands and thousands of miles of thick and heavy, slushy, gas-filled ice.

THOMAS: Like thousands of miles of floating Slurpee.

RAZ: Well, I'm not entirely sure what it would be like, but I thought I'd try and imagine what it could be like, you know, to skydive into Neptune or Uranus and travel deep inside.

THOMAS: Yeah, I'm not sure that would actually be physically possible.

RAZ: Well...

THOMAS: Plus, Neptune is freezing, like minus 218 degrees Celsius or something crazy like that. And the absolute coldest it's ever been on Earth was minus 94 degrees Celsius. And that was on an Antarctica.

RAZ: Wow, it got that cold on an Antarctica?

THOMAS: You bet your Birkenstocks it did.

RAZ: Well, it is probably true, Mindy, that the gas and slush are so thick that no one would survive that journey. And besides, I just discovered that once you get to the core of these giant ice balls, it's actually hot, like, 7,000-degrees-Celsius hot.

THOMAS: Wait a minute. Where's my climate almanac? Oh, here it is. All right, let me just open this up. Ah, the pages are stuck together.

RAZ: Yeah.

THOMAS: You want some gum?

RAZ: Yeah, I...

THOMAS: Got it. Let me see here. According to my climate almanac here, yes, the hottest temperature ever recorded on planet Earth was 58 degrees Celsius, or about 137 degrees Fahrenheit, and that was in Bolivia in 2012.

RAZ: So you can imagine what would happen to you if you got anywhere near 7,000 degrees Celsius.

THOMAS: Yeah. Could you say, turn to dust?

RAZ: Yeah, poof.

THOMAS: But if the outer layers of Neptune are so freezing cold and the inside is so hot, well, according to my calculations - let's see here - that's a temperature difference of 7,212 degrees. So how is that possible?

RAZ: Well, according to this study I'm reading about Neptune and Uranus, the reason it's so, so hot at the center of these planets is because all of that ice and slush and hydrogen and helium and methane and ammonia is heavy. And all of that heavy weight creates pressure.

THOMAS: And pressure creates heat.

RAZ: Yes.

THOMAS: But then why wouldn't that fiery core melt the slushy ice all around it?

RAZ: Well, it's because there are thousands and thousands and thousands of miles of freezing cold gas and ice all around it. It's just too much ice to be affected by the hot core of the planet.

THOMAS: OK, got it. So can we drink these Slurpees now, or yes?

RAZ: Well, they aren't the healthiest of beverages, so maybe we should just...

THOMAS: (Slurping). This Sour Patch flavor is bonkerballs (ph).

RAZ: ...Throw them away.

THOMAS: (Slurping) Refreshing. Don't you just love the taste of science?

RAZ: Well, maybe next time I should just use plain old crushed ice.

THOMAS: Yes, and then we can do this experiment with snow cones.

RAZ: Hey, speaking of snow cones, you know how those little slivers of ice kind of look like sparkly diamonds?

THOMAS: Not the first thing that comes to mind, but I guess, yeah.

RAZ: Well, Mindy, I happened to come across a study that was just published in the journal Nature Astrophysics written by a physicist.


THOMAS: Timeout. A physicist is a scientist who studies the matter and particles and energy in our universe. And the most famous physicist of all is Albert Einstein, who's known for the theory of relativity and having a sweet 'do. Time in.


RAZ: And this particular physicist from Germany, named Dominik Kraus, was able to test out a theory about Neptune and Uranus.

THOMAS: And so what was the theory?

RAZ: Well, scientists have long believed that you get a particularly interesting type of rain on these planets.

THOMAS: Yeah, go on.

RAZ: Well, if you were able to hang out inside the atmospheres of Uranus and Neptune, it would rain...

THOMAS: (Yelling) Tacos. What? No.

GUY RAZ AND MINDY THOMAS: (Singing) It's raining tacos from out of the sky - tacos, don't even know why. Just open your mouth...

THOMAS: (Singing) And close your eyes.

RAZ: No, no, no, no, no.

THOMAS: What? What? Sorry.

RAZ: Not tacos, no.

THOMAS: Not - I'm so - no, right, right.

RAZ: Mindy, what's raining down on Neptune and Uranus is even better than tacos.

THOMAS: Guy Raz, you take those words out of your mouth right now. You know there's nothing better than tacos. In fact, I think I want some right now. Hey, Reggie (ph), come here, you spicy old bird. Do me a favor and fly down to the tacosaurus (ph) truck and pick me up a dozen hard shells with the hot sauce. Just put it on my tab, OK.

RAZ: Hey, can I have one of those tacos?

THOMAS: Aw, of course you can, little buddy. That's what friends are for.

RAZ: Oh, right.

THOMAS: But you're kind of derailing the conversation.

RAZ: Yeah, I...

THOMAS: I'm still waiting to find out what it's raining on Uranus and Neptune.

RAZ: Oh, oh, right. Well, if you were to go to Neptune or Uranus and somehow manage to go deep inside their atmospheres, it would rain...


RAZ: It would rain...


RAZ: It would rain...

THOMAS: OK, I'm not doing this anymore.

RAZ: Mindy, it would rain tacos.

THOMAS: What? Guy Raz, I already guessed that.

RAZ: Oh, oh, sorry, I was confused. I meant diamonds. It would rain diamonds on Neptune and Uranus.

THOMAS: Oh, raining diamonds. OK, yeah, and I guess the next thing you're going to tell me is that that diamond rain is actually the tooths of space unicorns.

RAZ: No, no unicorns. But, yes, diamond rain.

THOMAS: OK, so let me just make sure I've got this straight. You're saying that when it rains on Neptune and Uranus, it sometimes rains diamonds?

RAZ: Yes, yes.

THOMAS: Like diamond-ring diamonds?

RAZ: Yes.

THOMAS: Like bling-bling diamonds?

RAZ: Yes.

THOMAS: Like diamonds-are-forever diamonds?

RAZ: Those are the ones.

THOMAS: Like diamonds as in diamonds and pearls?

RAZ: Mindy, I'm talking D to the I to the A to the M, O to the N to the D to the S - diamonds.

THOMAS: Wait a minute. That means that if we could just get to Neptune or Uranus to grab some of those diamonds, we could be - we could be millionaires, Guy Raz, bamillionaires (ph). Hey, Reggie, go find your subzero parka. We're flying to Neptune.

RAZ: Mindy?


RAZ: You sent Reggie to get tacos.

THOMAS: Oh, man, I forgot.

RAZ: And besides, Neptune is so far away. It would take about 12 years to get there from here on Earth. So forget about it.

THOMAS: OK, fine. But how is it possible that it rains diamonds on Neptune and Uranus?

RAZ: Well, so this is the amazing part.

THOMAS: I'm listening.

RAZ: You know how earlier I mentioned how all of that pressure from the ice and slush and gases on these planets makes the center, or the core, really, really hot?


RAZ: Well, it turns out that that same pressure creates diamonds.


RAZ: I know - incredible, right?

THOMAS: Yeah. Well, how does it work?

RAZ: Well, you know how I was telling you about that thick layer of slush that surrounds these two planets?


RAZ: Well, that slush is full of elements called hydrogen and carbon - these teeny-tiny atoms that are invisible to the human eye but are the building blocks of all life.

THOMAS: Yeah, even we humans have atoms inside of us.

RAZ: Mindy, we humans are mostly made up of hydrogen, oxygen and carbon. In fact, the average human contains 7 billion billion billion atoms.

THOMAS: And wait a minute. Aren't diamonds also made out of carbon?

RAZ: Yes. And when carbon comes under intense pressure, like the kind of pressure under all that ice and slush on Neptune and Uranus, well, that carbon can crystallize and form into a diamond.

THOMAS: And with all that pressure on those planets and all that carbon, you get lots and lots of diamonds.

RAZ: Mindy, diamonds that fall towards the core of those planets.

THOMAS: That's the diamond rain.

RAZ: Exactumundo (ph).


RAZ: Except...

THOMAS: Oh, man.

RAZ: ...Well, until very recently, scientists thought this is what happens on Neptune and Uranus, but they hadn't proved that it actually does happen.

THOMAS: So how do they prove it?

RAZ: Well, this physicist I mentioned earlier, Dominik Kraus, he ran an experiment to try and prove that diamond rain exists on these planets.

THOMAS: And what was the experiment?

RAZ: Well, Dominik and a team of scientists got a thick block of polystyrene. It's a kind of plastic made from hydrogen and carbon.

THOMAS: Just like the atmospheres of Uranus and Neptune.

RAZ: Yes. And then these scientists took two different types of laser beams. One was an X-ray laser, and the other was an optical laser. And they blasted these beams right through the block of plastic.

THOMAS: Wow, I hope they took safety precautions.

RAZ: They did, for sure, because those laser blasts created so much pressure and heat in the polystyrene - actually, as hot as the core of Neptune, Mindy - that it forced the carbon in the polystyrene to separate and form teeny, almost microscopic diamonds.

THOMAS: So it's the same process that happens on Neptune and Uranus.

RAZ: Yes, except for one big difference.

THOMAS: What's the big difference?

RAZ: Well, on those two planets, the diamonds are formed over thousands of years, so it's likely, Mindy, that the diamonds produced on Neptune and Uranus are actually giant diamonds, like boulder-sized diamonds.

THOMAS: What? - boulder-sized diamonds?

RAZ: Yeah, but probably too big for your average ring.

THOMAS: But maybe if I used my shrink wand.

RAZ: No, Mindy, please, please, don't get any ideas.

THOMAS: Oh, looks like Reggie's back with our tacos.

RAZ: Well, sorry he couldn't bring you any space diamonds.

THOMAS: No big deal. Plus, you know what I always say. Tacos are a girl's best friend. Here, want a bite?

RAZ: Sure. I love this orange cheese on top.

THOMAS: Hey, that's nacho cheese.


THE POP UPS: (Singing) Wow in the world.

THOMAS: We interrupt this program for a special Wow News weather report. Live from Planet Rainbow is reporter Cora (ph) on the scene. Cora.

CORA: Thanks, Mindy. There is a bird hurricane on Planet Rainbow. The birds are flapping really hard to make strong winds. The temperature is 60 degrees, but you might not want to go outside because the birds are going crazy.

THOMAS: And, Cora, what do you anticipate could happen with these crazy birds?

CORA: You might get bopped in the head.

THOMAS: Ouch. Well, we do hope the citizens of Planet Rainbow will be mindful of those crazy flapping birds. Cora, can you tell us what to expect in the forecast on Planet Rainbow for next week?

CORA: The forecast for next week is 70 degrees. It'll be very sunny with a chance of rainbows. Don't spend too much time texting on your phones. Go outside and enjoy the rainbows. Back to you, Mindy.

THOMAS: Live on the scene from Planet Rainbow, that was Cora with a special weather report. For Wow News, I'm Mindy Thomas with the who, what, when, where, why, how and wow in the world.


THE POP UPS: (Singing) Wow in the world.

THOMAS: Hey, thanks so much for listening to WOW IN THE WORLD this week.

RAZ: And parents, if you want to continue the conversation with your kids, we've posted some questions about this episode at our website,

THOMAS: And while you're there, you can find links to some of the sources we used to tell our stories this week.

RAZ: Also, we love hearing from you. You can write us at

THOMAS: Today's show was produced by Michelle Darling (ph) standing in for Jed Anderson (ph). Say hello, Michelle.


RAZ: Our theme song, "Wow In The World," was written and performed by The Pop Ups. Check them out at

THOMAS: Special thanks to Meredith Halpern-Ranzer, Jessica Body (ph), Chelsea Erson (ph) and Alex Hurley (ph) for helping to make this show possible. And a big shoutout to our kid reporter Cora for that special weather report from Planet Rainbow. Cora, you, my friend, are sunny with a 100 percent chance of awesome.

Also, we love hearing what's been wowing you. For a chance to be featured on an upcoming Thursday episode, have your grown-ups help you share something that's recently wowed your world by dialing 1-888-7-WOW-WOW. Thanks again for listening, subscribing and telling your friends about our show. We'll be back for a brand new Thursday edition. In the meantime, go forth and find your own wow in the world.


THE POP UPS: (Singing) Wow in the world. Wow in the world. Wow in the world. Wow in the world. Wow in the world. Wow in the world.

UNIDENTIFIED CHILD: WOW IN THE WORLD was made by Tinkercast and sent to you by NPR.

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