- ( grunts ) - ( laughs )

Dan: This is the Strokkur Geyser.

It goes off every five to ten minutes.

Oh! That was a good one.

Dan: Oh, that's big there, look at that.

Gav: That is massive.

Now I've got something different in mind.

Of all the Phantoms we've ever used,

this is the biggest.

Dan: I'm nervous for his drone and the camera.

Might get hit.

Holy crap.

Oh! Jesus Christ!

( chuckles )

Well, looking back on that,

I think that was the most challenging conditions

I've ever shot in.

And it smelled really eggy.

Smells a bit like eggs.

Sorry, that was me, that one.

- Oh, was that you? - Yeah.

By far the sketchiest position

that Phantom camera has ever been in

is hovering above a hole in the Earth

and then getting battered with water.

Dan: Oh!

Jesus Christ!

Holy crap.

The amount of stress running through my body

- when I was watching that. - Oh, God.

It's quite cool that we had the opportunity to have the camera

flying above what we were filming.

- Yeah, it's never been that high, ever. - No.

I also thought it would be very cool if we brought along

a thermal camera to see the difference in temperature

between us and the water, so let's take a look at that.

Would you like to tell us about this camera?

Yeah, this is a FLIR thermal imaging camera.

This is actually a cold camera

and what is basically does, it measures temperatures.

Dan: This is like 80 to 100 degrees.

Rudd: Yeah, basically every pixel is a temperature measurement,

so you can be really detailed on what you want to measure.

So should we have it so that it's further back and I'm in the frame?

- So I'm just shivering... - Yeah, let's see what that looks like.

Shivering and then, yeah.

Well, I guess I'm not operating, I can be in there with you.

- Oh, yeah, okay. Yeah. - Hey.

All right, let's do it.

- It's a bit cold, isn't it? - It's pretty chilly.

- What is it, like one degree? - Something like that.

- And it's raining as well. - Yeah.

Shouldn't be long though until it goes off.

I like this one 'cause it's only like every five minutes

this one goes off.

Check this out, ready?

- Oh! - There you go.

All right, how was that?

( chuckles ) Look at our little faces.

Dan: ( laughs ) I look like I'm evil.

My eyes are warmer than the rest of my face.

Gav: You're leaking heat through your eyes and neck.

Oh, yeah.

- Dan: Oh, that's crazy. - Gav: Isn't that cool?

- Yeah, that's wicked. - Then all the steam.

- That's really cool. - Yeah.

And this is the software that the FLIR cameras use.

So we can actually see some values.

Firstly, let's just see how cold my nose was.

56...

What is that guff number?

Fahrenheit, you got to change it, you got to change it.

Let's get on Celsius.

I like how your nose is so much colder than your face

'cause it's so far away from the blood flow.

Got a 14 degree nose.

( Dan laughs )

But my eyelids are 23.

All right, let's play on.

And what you got to remember is it's actually really cold outside,

so it's so quick to turn into cool water.

You see how quickly it fades off

and becomes your greens and your blues.

It's wicked.

Looks like a rainbow got nuked.

It does.

Yeah, all this stuff that's still bubbling

is the hottest.

Yeah, 60. 70 degrees there.

Oh, something I've always wanted to find out.

Yeah?

Gav: Let's have a quick look at your heart.

- Ooh. - Cold as ice.

- Cold as ice, five degrees. - Yeah.

With an asterisk so it's probably like...

Can't, it's too cold.

'Cause we filmed it in RAW,

it meant that we can edit this as we're going

in this software.

Well, let's see what the highest temperature it hits

through the whole thing.

Spot in-- 87, that's pretty high.

86, 85, 83, 82, it's going down.

So at the beginning of the eruption

was the highest temperature.

Around here, yeah.

87.

87.9, about 88.

88, and that's probably... yeah, around there.

It's the hottest it's been.

So pretty much as soon as it's burst its bubble,

that's when it's the highest.

- Gav: All right. - Dan: It immediately turns cooler.

Think we've learned a lot of good stuff there.

So I've never actually seen anything like a geyser in real life.

It's kinda surreal.

Although, I don't actually know what's happening, so...

I mean, we spent all day there and it's still kinda confusing how that worked.

- A complete mystery. - Yeah.

So now we've got John Cotter with us,

who's a professor of geography and environmental science,

who can hopefully take us through exactly what's happening.

We also have this lovely experiment.

Do you want to run us through this?

( music playing )

Okay, well, water's gonna be flowing downhill.

And as it flows downhill, it's gonna start seeping into the ground.

So as it's coming down,

deep below there has to be some kind of a boiler.

And so that water's gonna get in there,

it's gonna start heating up.

And once that starts boiling like that,

it's gonna start getting bigger and bigger and bigger.

And as it rises, that heavier, more dense water

is just gonna come and flow underneath it,

and that gives it a little bit more spring.

And once that spring starts, you've got a jet heading upstream.

It's amazing that they're so deep and so narrow.

- Yeah. - Gav: It's Phantom time.

John, do you want to explain how this experiment works for us?

Okay, let's start with the hot plate down here,

this represents the magma

that's gonna be heating up the water.

And these bubbles are getting bigger and bigger

and coalescing at the top of the beaker.

Once that bubble gets big enough,

it's gonna have enough momentum to start climbing.

So if you're on the surface looking down on this thing,

what you're gonna see is this bubble starting to rise

that tells you that blast is right on the way.

Man: Here we go, back up.

- And... - Oh, about to go.

- Oh! - John: Spectacular.

Why did we go to Iceland?

- Sounds like you after a curry. - Yeah, I was gonna say the same thing,

I was gonna make the same joke, but I thought it'd be in poor taste.

Gav: And you see the water go back down, that was cool.

So it's gonna do it again and build up again

for a second eruption.

( music playing )

Oh, yeah. It's a very realistic scale.

Dan: Wait, why am I way fatter than you are?

- Gav: I don't know. - Dan: I just spotted that.

Someone's made like a-- whoa!

Gav: I like how oddly similar this tiny experiment is.

Dan: It's exactly the same.

It was the same thing, you get the bubbles of water coming up,

building up and then erupting, it's exactly the same.

Gav: That's what's great about the universe,

- it's quite consistent. - Dan: Yeah, that's true.

Gav: So, John, is this exactly what you expected from this experiment?

John: I think it's very good

except these tourists need to stand a little further away.

Gav: They're too close, oh, yeah.

( laughter )

Well, we cleaned the ceiling.

- With boiling hot water. - It's spotless now.

Yeah, it's great. Thanks very much, John, for your help.

- Appreciate it. - I actually really feel like I've learned something there.

Glad to have had a chance to meet you. Take care.

- Very nice to meet you too. - Thanks.

Hopefully you enjoyed that episode.

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Why did we only just think of this?

- That's great. - Yeah.

Doesn't really work the way we pronounce it, but...

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