> temp > à-trier > spinning-sphere-of-molten-sodium-to-understand-the-earth-magnetic-field-veritasium

Spinning Sphere of Molten Sodium

Veritasium - 2018-07-14

An experiment on how turbulent convection in Earth's core makes a magnetic field
Get a free audiobook with a free 30 day trial at  http://www.audible.com/Veritasium or text Veritasium to 500-500

Huge thanks to Prof. Dan Lathrop and team: http://ve42.co/Lathrop

Companion video to explain Earth's magnetic fields in more detail:
https://youtu.be/lWHxmJf6U3M

Australians! I'm on my way. I'll be doing live shows in Perth, Sydney and Melbourne. Details and tickets here: http://ve42.co/tour

Find out more about the film Vitamania: http://ve42.co/VITA

Special thanks to Brady Haran and Periodic Videos for sodium vs water footage. Original clip is here: 
https://www.youtube.com/watch?v=mzEOL-N2cbw

Special thanks to Patreon supporters:
Donal Botkin, Michael Krugman, Jeff Straathof, Zach Mueller, Ron Neal, Nathan Hansen, Yildiz Kabaran, Terrance Snow, Stan Presolski

I learned a lot in making this video and the one on my second channel with Prof. Jon Arnou. I changed a lot of my preconceptions, specifically I thought:

1. That the Earth's magnetic field was a passive thing - it shouldn't need a continuous input of energy to maintain itself (that seemed reasonable to me because the magnetic field has been around for a long time and it seems mostly stable). But as it turns out, the Earth is a giant electromagnet, and so of course those currents dissipate their energy as they encounter resistance in the liquid metal through which they flow. So the energy to continuously create these currents comes from the kinetic energy of the liquid metal flows in the Earth's outer core.

2. If it's convection, I'm thinking hot things rising, cooler things falling. But apparently the main effect driving convection is the compositional differences at the boundary with the Earth's inner core. This is because of the differential freezing at the boundary. Things like iron freeze into the inner core, while elements like sulfur do not. Hence the pockets of lighter material which then rise outwards.

3. I didn't get why the fluid motion was necessary for the generation of the magnetic field. I mean if it's a conducting liquid, it can conduct currents whether it moves or not. But the key is that the liquid metal can 'trap' magnetic fields. I imagine this like how iron channels magnetic fields. Then once these fields are channeled, they can be pulled and stretched, making more magnetic field.

4. Fluids operate very differently in rotating frames of reference. This is something I didn't intuitively grasp. But, as fluids move from the inner core outwards, those particles are moving much more slowly in the direction of rotation than the matter that has been there for a long time, which means the convection currents get deflected and form helices.

Music by Kevin MacLeod http://incompetech.com Brandenburg Concerto No4

Alexander Englebert - 2019-04-23

This guy definitely sounds like he has had to defend the legitimacy of his lab many times.

Sunriser - 2020-02-23

@Damon D Ramsey magnets manipulate magnetic fields not gravity they are 2 completely separate things. Yes you can make things float by using a magnet but its not making the force of gravity go in the opposite direction all you are doing is applying a magnetic force that is stronger than the force of gravity and pointing it in the opposite direction making the thing float. Gravity comes from things having mass. Magnetism/electricity comes from things having charges in them like electrons.

Damon D Ramsey - 2020-02-27

@Sunriser With your limited definition then, anti-gravity is impossible. Gravity is simply the "attractive" effect on one mass on another and vice versa on a macro scale. Air travel, to me, is technically anti-gravity with + & - G forces. Mass, velocity, acceleration, inertia, angle of attack. All used to counteract the inevitable and irreversible effect of Earth's gravity (extremely weak in comparison to other forces, although strong on an anthropomorphic scale). Electromagnetism is the key to new technologies, whether "anti-gravity", fusion, etc.

Sunriser - 2020-02-27

@Damon D Ramsey you cant have negative gravity like u have positive/negative charge and electric forces since there is no "negative" mass particle

Andrew Fisher - 2020-03-07

@Sunriser https://en.m.wikipedia.org/wiki/Exotic_matter?wprov=sfla1

Sunriser - 2020-03-07

@Andrew Fisher i know its a thing but you cant actually make it

Blockhead134 - 2019-01-11

Lets just skip over "the magnetic field is dying and we don't know why"

Bryan Skrenes - 2019-10-21

Right?!!!!!!!!!

maruftim - 2020-02-14

yeah lol

Caleb Tidwell - 2020-02-21

Decrease in intensity =/= dying magnetic field, but I understand the concern. What's not mentioned here is that while the magnetic field is important for life on Earth, there's no correlation between changes in the magnetosphere and extinction/mass die-off events. There's a healthy concern about how electronics will behave if/when an event happens (i.e. solar storm, pole inversion, etc), but magnets, however they work, are not going to kill you.

CJR - 2020-02-23

@Caleb Tidwell
If the decrease in intensity continues at the current loss per year, there will be only x amount of years before there's nothing left. Maybe not "dead" but certainly not there. So if your argument is about correlation/causation I understand what your trying to say. The problem that we can track What is happening but we cant explain Why it is happening. But his point is perfectly valid in the context he was using.

Tee Se - 2020-03-22

@CJR so i dont dont have alot of knowdlege on this particular matter but i dont know hot to tell when a commented is a psudeo intellectual and when they actually know what their talking about you should try and learn that skill, because untill you commented it was 1:1 ratio but with your comment the dunnig krugger affect is present in 200% of the comments disgussing changes in the magnetic field

CapnKayso 823 - 2018-12-03

"Describe your life in two words."
Me: "Modestly catastrophic."

John Apple - 2019-06-24

"gamer life" also "no life"
"kil me"

Ferociously Malicious Rain - 2019-07-17

Weeaboo no-life

Jeff Lindeman - 2019-08-14

Woof!

Steve Thea - 2019-10-09

@biggreenleaf @65259840 Audrina writes...
["see what you are drawn to. Ask about bullying policies, extra curricular activities etc."]
Drawn to..what exactly? I hit up a few Schools today looks to me if the grounds are well-kept, friendly staff encounters and well-behaved pupils gives me a positive first impression (Or am I being too naive/easy to please?)
- I even ask some kids Where's The Office? and lightly notice how they respond.
Have yet to hear back for some ACTUAL tours :)

And thanks for reminding me to ask Bully policies / activities.

@65261296 Spannerr writes...
["I know some schools near me offer really solid music and sports programs at the sacrifice of really quality education, while others do just the opposite."]

Zack Lee - 2020-02-15

Mild disappointment

TheFlerffyBurr - 2019-03-13

"Back up plan is put it out with cryogenics... it actually works great!"

ARE YOU IMPLYING, SIR, THAT YOUVE HAD TO USE THE EXTINGUISHER?

Jared - 2019-12-22

Of course. Testing professor. Testing

Kevin Vermeer - 2020-02-21

What I want to know is what happens after the nitrogen has evaporated and you've got a giant blob of solid sodium across the floor of the lab? Do you pour mineral oil over it and chunk it up with a concrete saw or something? Seems like a giant piece of solid sodium is only slightly better than a giant flow of liquid sodium...

Felix Roux - 2020-02-22

He could have tried with a miniature version.

CJR - 2020-02-23

@Benjamin Joshua Beggs
What makes you say probably not? Based on what?

Benjamin Joshua Beggs - 2020-02-23

@CJR You are about 8 months late, so I don't quite remember what this video was even about, but looking at it now I don't see how leidenfrost even matters here. Wasn't this about whether or not it would put out the fire? And no, I certainly don't remember where I got that info from.

Yannis Constantinides - 2018-08-30

1:48
>Emphasizes the importance of safety
>Has power strip hanging by the cords plugged into it

RainbowXD - 2019-09-15

No worries ... It was pulled in by the magnetic force and wrapped around many times... Thats how the cryogenics were tested

The Blue Kommandant - 2019-10-01

If you look it's actually attached to a bracket.

Daryl Loth - 2019-11-11

I have a feeling it is for the temporary lighting used to film the video. It seems to be partially illuminated from a low angle which doesn't seem normal. Just a guess.

Cody Tanksley - 2019-11-27

This is every experimental physics lab I've ever been in lol

David Zachmeyer - 2019-12-29

@The Blue Kommandant But the bracket isn't attached to anything else...

Studio Azarath - 2019-03-10

Weird to click on this video and suddenly see my old neighbor.

OhMyAwSoMe - 2020-02-28

@over00lord Unknown no

Burton Meat-square - 2020-03-10

@over00lord Unknown no

Mr.Skull: The King of creativity - 2020-03-12

@over00lord Unknown no

Ramz Malubay - 2020-03-15

@over00lord Unknown no

Lawrence McLane - 2020-03-20

over00lord Unknown no

Red Oktopus - 2019-05-30

5:40 There is no way we'll ever know which dinosaur comic that was stuck to the machinery

Quiet Kiwi - 2019-07-15

That comment brought me joy thank you.

Aleksander Lenartowicz - 2019-10-21

with enough manhours we can find out. I recognize the style and know the artist, its just a matter of checking every comic for similarity :)

Rogue Trooper - 2019-11-11

It's a blank comic strip that you can add your own words to, there are loads of versions of it out there (just do a search for dinosaur comic strip and you will see), so you're most likely correct in saying we will never know. :)

KeanuBodypillo g - 2019-11-16

@Rogue Trooper thanks!

Bergius - 2020-02-05

Parody Week: Dinosaur Comics by XKCD
https://xkcd.com/145/

waffleless - 2018-09-14

How fast does that sphere need to spin to get you guys to start calling it “natrium”?

David Furor Curser - 2019-06-12

Before the scientist pulls the lever to kill off the fire, he looks at it over his shoulder and says, "Chill."

Avocedo 。 - 2020-02-18

Heavy breathing

Jerry Oak - 2020-02-25

... and then this plays on the background
https://youtu.be/NXCaHq-F0m4?t=460

Matthew Solo - 2018-07-18

Modestly catastrophic... my new favourite tag line :))))

Mike Palmer - 2019-03-02

I like that statement. "Modestly catastrophic". Lol

iliketrains0pwned - 2018-07-19

I love how they have all these fail safes to prevent the sodium from going boom, but they still left that live power strip hanging out the door from its cords 1:48 XD

Steven Brock - 2019-07-05

Overestimating the risk of electrical fire is common. If that sodium comes out, it would make an electrical fire look like a butane lighter. Priorities for safety:
molten sodium >>>>>>>>>>>>>>> electrical safety.

Real Engineering - 2018-07-14

This guy is a bad ass. Great interviewee

Giorgi Khechinashvili - 2019-05-30

Can we upgrade Mars magnetic field? With creating electro magnetic field...

Shinigami Shinto - 2019-08-31

totally agree :D he makes the subject even more interesting the way he talks, his passion and explanations are so clear!

Funny Memes - 2019-10-06

Cool... Real Engineering watches Veritasium too!

CJR - 2020-02-23

@Idjles Erle
Actually he didnt give a great answer to that question. Its the part when Veritasium says that what the guy is saying is counter intuitive, because it is. You can not create energy out of nothing. A tickle of energy can create a tickles worth of energy , often a little less. Its the law of thermodynamics. Its the equivalent of saying free energy machines really work. (Hint : they do not) there's something else going on that the guy couldnt seem to answer, why? I couldnt say. But the energy witnessed is energy converted from another type of enegy

Idjles Erle - 2020-02-23

CJR you are going on a tangent. I have a degree in quantum physics - I don’t need a lecture on conservation. I just said I liked the world “tickle”. That spinning ball has a lot of kinetic energy, and it only requires a “tickle” somewhere for kinetic energy to start to convert to electromagnetic energy. No one has an issue with conservation - we know it’s there. Conversion is what this experiment is all about.

Starshot - 2018-07-25

Another huge question in my life answered

darthspeaks - 2019-11-14

"Dont worry, they have a huge pool of water below it to put it out if it breaks."
I think we'll go with liquid nitrogen...

Michb3ck - 2018-07-18

4:51, so its like an amplifier for "infinitesimal" magnetic fields?

MyuFoxable - 2018-07-27

I like how there is a dinosaur comic giving instructions about the machine.

The Science Biome - 2018-07-14

I wish Veritasium wasn’t such a rare element.






How can we find more?!

Scooters Videos - 2018-07-23

The sun should play a role in the earth's magnetic field, and why it rotates and orbits in the direction it does.

Babylonian Debonair - 2018-07-26

The Science Biome YOU LIKE AND SUBSCRIBE

Zack Toor - 2019-02-20

I hear there's a lot found near unobtainium veins...

Gabriel Kellar - 2019-02-23

by rockin the merch

Dominic Doherty - 2019-11-29

Pandora

Joe Fulton - 2018-07-19

Haha this is awesome. I've stood up there on top of the sodium ball, our lab is right next to this. Modest catastrophe means our project gets wiped out!

paraiks - 2018-07-26

2:23 his shirt matches the background

Dan J - 2019-03-20

did he just say the earth's magnetic field has reduced by 10% in the last 100 years? ... thats scary

Yora - 2019-04-17

It is cause for concern, which is why they are studying these things. It probably is something completely natural that has happened to the Earth many many times over the past billions of years. It should be no threat to life on Earth.
But up until 100 years ago, we didn't have sensitive electronics, and those can really suffer very badly if the magnetic field gets weaker in keeping charged particles from the sun away from Earth. If in the future the magnetic field will go below a certain level, we will have to design our future electronics differently so they can handle it. But for that we need to know how weak the magnetic field will get before it gets stronger again, and how much time we will have before that.
That's why they are doing this research.

Deranged Chicken - 2019-10-29

He seems moderately calm about the impending catastrophic disaster of the weakening of the earths magnetic field. all though there is a silver lining to our magnetosphere fading and disappearing... it will be the greatest ever 'we told you so' to the flat earthers...

Ferenc Gazdag - 2020-03-19

We are not sure if it will continue at this pace, and predicting it is not yet possible. When you see the night fall for the first time, you might think, that your star is fading. This is the reason why this lab exists.

A Vsaucy Boi - 2018-07-15

Now I really want to see liquid nitrogen put out molten sodium

Steven Brock - 2019-07-05

@Corey Wood Of course. You wouldn't design a fail-safe without knowing it works.

Steven Brock - 2019-07-05

@hokiepokie More likely the copyright owner demanded its takedown. The government has very little to do with YouTube.

hokiepokie - 2019-07-07

+@Steven Brock ...
I can't remember who did it, and this was years and years ago.... But it was on a channel similar to King of Random and such.
I'm telling you, that I've NEVER seen another video like it!!! This experiment went so crazy, that the people that were doing it were luckily wayyyyyyyyy downrange when Mt. Vesuvius met Nagasaki!!!! It was simple ingredients, simple setup, and MAJOR CARNAGE!!
Cheers!

hokiepokie - 2019-07-07

+@Steven Brock ...
For comparison, this is child's play compared to that particular video....
https://youtu.be/KJBJgxPI3yg

Rabo Karabekian - 2019-10-20

@Corey Wood Yuuhh. If you can't see sumthin, it's don't axist. Smart peepul sure is stoopid.

Leandro Ferreira - 2019-11-15

This reminds me of the "black hole engine" in Event Horizon

Gene Hall - 2020-02-13

Definitely a movie that can induce nightmares.

Joe Chavez - 2018-07-20

Just one step closer in learning how to build the perfect spaceship: Earth

Volvith - 2019-03-05

It's like...
The more i learn about the intricate systems necessary to maintain life on earth, the more i get the feeling that, yes..
... Yes, we are alone.

Chase Moeller - 2019-07-06

@Steven Brock we have no reason to believe matter does not go beyond what we can observe

Totto87 - 2019-08-10

@Chase Moeller Given the big bang theory, the universe can't be infinite. There is a set number of atoms in the universe that was stored within that big object before the big bang, expanding and stretching outwards as we theorize it now. For all we know, there might come a time where an implosion occurs. Much like after an explosion, the vacuum drags air and objects inward again toward the epicentre of the big bang, wherever it might be. I don't have the brain power to prove any of this with calculations or anything like that but I love the thoughts behind the different hypothesises and theorems.

Chase Moeller - 2019-08-10

@Totto87 that's not nessisarly how the big bang works, the singularly can be considered infinitely dense

roland van der Vegt - 2019-08-22

@Chase Moeller space itself might be infite, but there is still a finite number of planets in the universe...

So no infinite changes for "systems to line up"

Gene Hall - 2020-02-13

Or maybe, more of a reason to think we are NOT alone ,and that it ,or they may just be forever beyond our perception. Because it or they have designed it this way.

polypumkins111 - 2019-01-28

This is amazing. If they could they perfect this and minimise it, could it like be use like in a space scarf to stop the radiation passing through it. That would be cool.

Mark Kmiecik - 2019-12-15

Yes, my new catch phrase: "Modestly catastrophic".

MediaSubliminal - 2019-08-08

Take a look, see those pearly whites! I ain't seen teeth that straight tweren't store bought.

kickinbackinOC - 2019-12-29

S.A., huh..lovely...I wrote a poem-
"If I were a boer,
I'd mak a plahn,
And get out of S. Africa,
As fast as I can"

AyeJayCee - 2018-08-22

that is one excited scientist.
Then again i'd be just as happy with a giant sphere of molten sodium

Robert McGarry - 2019-02-07

T-shirt: "Modestly catastrophic."

Ducati Dave - 2019-05-21

The loss of Earth's magnetosphere. Just great. Add that to the other pending world ending events.

Leonardo Vergara - 2020-03-12

How is it going? !

SermonFapple - 2020-03-11

Love the child proof padding around the giant mass of sodium lol

Hooked Up - 2020-01-22

2:05 no big deal just a basic power strip leading to our 80 mph spinning sphere lol

Fábio Duarte - 2018-07-14

#ModestlyCatastrophic

evanplanas - 2018-07-16

great band name....

evanplanas - 2018-07-16

great band name....

tiny derp potato - 2018-07-17

we need a t-shirt

L Kahfi - 2019-01-16

1:59 I though someone laughing behind me

Yora - 2019-04-17

"and everything is just chilled."

The best way to contain a catastrophhic disaster.

C M - 2019-10-04

They must have completed "Die Glocke."

Boomchacle - 2018-09-06

"it actually works great" Has he had to do this before?

Jason Carto - 2018-07-14

These are scientists we need.
"Yea its risky. Yes it could be a catastraphy. But were going to try it. And we've even invented new ways to prevent things going really really baddy"
Bold science is best science.

Jon M - 2018-07-16

Charles Lynch Its a symptom of the cult of religion that science has become.

loke703 - 2019-06-14

I fear one day you will regret this comment.
Is strong weather the best weather?

midgame jeff - 2019-06-20

@loke703 if we were the weather it would be good

Nick - 2020-02-21

4:48 Legasov: Completely normal phenomenon.

Carlos Vieira - 2019-06-21

4:47 Dinosaur Comics spotted. I like this guy even more.

Christopher Milne - 2018-08-02

When a scientist says "kill-AH-miter," instead of "KEE-low-meter" my eyes roll back in my head and I smell a bad smell.

jacob anderson - 2019-10-24

I watched this recommended video, at 3:45 a.m, without having a single clue of what it was really about, nor any real reason... I think I have a problem.

xerox3333 - 2018-07-17

Try explaining this to a Flat Earther

SedoKai - 2019-11-07

Try finding a real flat-earther. A real one. Not just someone who's trolling you.

darthspeaks - 2019-11-14

Their version of the experiment is a giant disc.

Edward Lulofs - 2019-12-23

@Jerome Lawson Nope. Firstly I agree the earth is round. Second, it's almost impossible for me to imagine it any other shape. Third, Flat earthers assume it's flat. Lastly, it's impossible for them to imagine it any other shape. ----- One word makes all the difference.

Perplexed Perceptions - 2020-01-28

Jaakko Fagerlund I guess you don’t know how much of Earth’s surface can be seen from the “space station.” Or else you wouldn’t have said that.

Valentin Degenne - 2020-02-18

I am not flat earther but couldn't a disk also have its 2d magnetic field also ? Just a thought

Luke Eckles - 2019-03-20

6:35 the dinosaur sign, I really want to know what it is haha.

aldo guzman - 2019-03-09

This video ended for me 13:30 in? Im thinking YouTubes algorithms leaked.

Hate Speaker Sargon Of akkad - 2019-05-21

Legend has it, Trevor Noa is a comedian.

Me - 2019-06-04

random but true

Marco Pohl - 2018-07-22

"modestly catastrophic" gotta remember that one