What Are the Northern Lights? | Neil deGrasse Tyson Explains...

What are the Northern Lights? On this explainer, Neil deGrasse Tyson and Chuck Nice discuss Earth’s magnetism and the aurora borealis. What makes the poles light up at night?
Will Earth’s poles flip? We discuss Earth’s precession (wobble), bob, and flip. Learn about the magnetic poles. Does your compass actually point to the magnetic north pole? Are the north pole and the magnetic north pole the same thing? Why do we even have a magnetic field? Discover Earth’s molten core, creating a dynamo, and why dead planets like Mars don’t have one. How often do Earth’s magnetic poles flip? Find out what magnets and aurora borealis have to do with each other. Will something bad happen if the poles do flip?
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Science meets pop culture on StarTalk! Astrophysicist & Hayden Planetarium director Neil deGrasse Tyson, his comic co-hosts, guest celebrities & scientists discuss astronomy, physics, and everything else about life in the universe. Keep Looking Up!
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0:00 - Introduction
0:24 - Earth’s Axis
1:49 - Magnetic Poles
5:21 - Earth’s Core
7:47 - Magnetic Field
9:40 - Aurora
12:08 - Closing Notes

[@StarTalk]

Magnets, how do they work?

[@CarolinaBassHunter]

You're asking me?!?! 😆

[@fritzelly7309]

I don't know but for some strange reason I'm finding myself attracted to this channel

[@AhldaiErdai]

They attrack and repel through being electrically charged

[@AsylumDWP]

One would think, a mixture of magic and God.

[@andro8206]

they visit the north and the south of poland and they enjoyed it just sayin

[@monteepython84]

I am having a terrible case of anxiety these days but listening to StarTalk gives me strength to confront it. Thank you Dr Tyson and Mr Nice.

[@JeandreCK]

You're enough! 💯 In every aspect of life. Don't give up because there's just 1 you!.... You are unique and amazing... You got this!....

[@monteepython84]

@@JeandreCK Thank you very much, my friend. That felt so good :) May the wind be always at your back!

[@paul9478]

smoke pot and listen to podcast..... thats what i do all the time... i do not have any anxieties or disorders just saying it

[@bethgoldman2560]

I’ve had the joy of seeing the Aurora Borealis in northern Maine in 1981. It was hues of green and red. What no one tells you there’s is a sound with it. To me…it sounds like a saw hit by a mallet….it was the highlight of my young adult life!

[@CricketsBay]

Yes, the 1st time I saw/heard a hillbilly playing a saw on KZbin, I recognized that sound. Hillbilly Saw Band is a thing, btw.

[@brandonsmith1838]

I saw red in the sky that was apart of it in Louisville Kentucky. In 2012

[@the5quatch]

The sounds of dancing plasma in the sky ❤❤❤

[@StarTalk]

Fascinating account!

[@tarmstrong9906]

That's wild. I didn't know that, wow 👂

[@Hugh_Jas]

"Pay what you owe, Santa!" made me laugh more than it should have.

[@osw330904]

3:08 bruh quoted the boondocks 🤣🤣😂 love it chuck!

[@carnitagroves7758]

Greetings from Ghana! ANOTHER awesome episode, gentlemen!! 👊🏾✊🏾

[@Teo117]

I will watch all of you explainers. Thank you

[@riparianlife97701]

No one ever asks HOW are the Northern Lights? 😔

[@loveli420]

😂😂😂😂😂😂

[@julianriviera5837]

I'll do you 1 better. Why are the Northern Lights??

[@CricketsBay]

No one ever asks how ARE the Northern Lights.

[@songOmatic]

"Just Chillin'. How's by you?"

[@Charlesb88]

They are feeling bit dim right now but things should brighten up soon and I expect some glowing news from them.🤣😂

[@akdas27]

Here I am attending my classes which I was supposed to attend when I was in school. Thank you teacher!!!

[@kariannecrysler640]

This one was fun. I am fortunate to live in a place you can see the northern lights occasionally. I wish everyone could see them at least once!😊

[@georgekavuvi9295]

😊😊😊

[@northernskies86]

I was lucky enough to witness an amazing auroral display in northern Minnesota about a month ago. They filled half the sky with green and purple pulsating lights, with some red in there too. Even auroras I saw in Iceland didn’t compare to this. Best night of my life.

[@lbthingsstuffmore9513]

That was sneaky Dr. Tyson! But pretty awesome!😂😂. Thank you for expanding our knowledge!💚🖖

[@IslandGirlKelly]

I have been so looking forward to you guys covering this subject. Many thanks. 🙏💚

[@michaelccopelandsr7120]

Neil and Chuck for 2024

[@francescos7361]

Thanks prof. De Grasse for sharing your studies with us . You are a great educator.

[@RamonLopez-kw1sl]

Except that his explanation of the aurora is wrong.

[@raiderjohnthemadbomber8666]

A wonderful way to explain centrifugal force, truly insightful.

[@ariannanorris-landry4428]

I lived in Alaska for 20 years and I had an affinity for knowing when the lights were going to come out and dance. My step sister had not seen them in 40 years until I called her one night and said get outside and look up. For native alaskans the northern lights are the campfires of the ancestors and the shadow and light play are caused by the ancestors dancing around the campfires. And yes there is a noise associated with them it's almost like a static and there's also a legend that you can whistle at the lights and it will make them change. Alaska was an amazing place to live

[@RhapsodicXStyle07]

Compass's point North because it's the Southern magnetic pole: Well yeah never thought of it like that but it's right. The Auroras also has sound: THEY HAVE WHAT!!!

[@StarTalk]

Thank you for sharing!

[@ariannanorris-landry4428]

Thank you for something that I've known right since 6th grade but nobody but Mr engelhardt would believe me

[@hello123s]

Step-sister, tonight we will see lights!

[@sanauj15]

4:12 I thought he was going to say that they make the compass's signs opposite of what they actually are. So the south magnetic pole of the compass reads as north and vice versa.

[@sprucetree2695]

I love star talk

[@CarolinaBassHunter]

I like when he said "They don't tell you that in the Boy Scouts." 😆

[@oof6520]

I remember when I was a kid back in the late 80's, my parents and I were driving back from North Carolina to Virginia late at night. When I looked up in the sky, I could see green, blue yellow 'clouds' passing through. The Aurora Borealis is the only thing that looks like what I saw....I've never seen it again since.

[@daverose4992]

Could it be that the inventor of the compass mislabeled the needle? It pointed in the northerly direction, so he called it the north pole when it is actually the south pole on the needle.

[@SteveC38]

I totally think the same thing👍

[@aeristone5941]

That's essentially exactly what Neil said...There's a geographic north and a magnetic north. They are different, and often confused to be the same, which is why Neil was repeatedly specifying magnetic north.

[@blakesemper4303]

This channel is so interesting and cool

[@susanjimenez5500]

Very interesting, like always! I always wonder why some magnets are weak and others are super strong...

[@thepandemicequation7100]

The science of the movie "The Core" comes to mind. Great explainer!

[@spencerkim5483]

I feel like I need to put on a protective cap so my mind stays intact when it’s blown.🤯

[@royalsquishy7058]

Awesome as always 👍

[@gsav1320]

This one was extra interesting. Thanks gentlemen!

[@MrBonners]

what I was taught in school was the phrase used was ' the North seeking pole '. The Magnetic pole is the reference being the field that generates the compass needle response so the north pointing needle end is the South pole of the magnet needle.

[@chancemeyers8502]

You know, I never though about that, but it makes so much sense. Because if you get two normal.magnet the two norther part of them push each other away. Thank you for telling .e that Neil. I love learning new fact. Thats why I watch this. You'll alway be my favorite scientist.

[@melindagibson8606]

What...nothing on the space collision today? Darn...I was hoping that was the topic today! But this is great!!!

[@dqixsoss7436]

There’s nothing to really say apart from ‘yay it collided’. We’ll know in a few months if it worked since by then there will be a noticeable difference in the asteroid’s orbit. They did a vid about the experiment fairly recently tho

[@bertsantens1211]

Hey Neil and Chuck, love your work I've been enjoying star talk for a few years now and I've been using a lot of the information I learn from it at work. I'm a professional Northern Lights Chaser. I guide and photograph Aurora Borealis in Northern Norway. A very interesting video about the changing of the magnetic pole but I feel like you only briefly mentioned the Aurora. It's such a complex phenomen that I think after 6 years I'm starting to understand but having a full explainer from you would help many people who do the same job I do, especially trainees who train with my company, and people who travel to see the Aurora. I was wondering if you're interested in doing a collaboration for a full length Aurora explainer?

[@peggynulsen1365]

Excellent suggestion, but not easy to do. In Fairbanks, Alaska there is a special museum devoted to the Northern Lights and puts together an amazing scientific lecture in a planetarium. Some of it was a bit over my head, but I came away with a decent lay persons understanding of how and why there are Northern Lights. Sounds like you have a very neat job.

[@bertsantens1211]

@@peggynulsen1365 exactly, there's a lot of info out there but it's tricky to understand, that's why it would be great to have Neil explain it. Every time he explains something I just get it. It's incredible 😊

[@RamonLopez-kw1sl]

Don't have Neil deGrasse Tyson explain the aurora until he knows what he is talking about. The explanation given here is wrong.

[@dawnhansen7886]

Star Talk =is Sooooooooo Gooooooood❕️

[@KrisRogos]

I would love a follow-up episode to this. What will actually happen when/if the magnetic poles flip in the next few decades? Is our infrastructure, sensitive electronic devices, GPS and other systems going to keep working as nothing happened?

[@wlyons15]

I learned something new today❤️ That’s all, thank you.

[@danielangus7944]

I wish they did more animated demonstrations, visually helps me remember it

[@robt.v.8688]

I suddenly have a craving for steamed hams

[@samirissanen6540]

Thanks for a great explainer. I just had the pleasure of watching awesome aurora borealis in northeastern Canada a few days ago. You did get one thing wrong, though. Santa doesn't live in the north pole. He lives in Finnish Lapland at a place called Korvatunturi 😄

[@dogussahin]

Great episode, I wish you also talked upon is aurora borealis dangerous for humans and technology?

[@FreddieBlaze]

Growing up as a very young kid I always admired & looked up to this brilliant and amazing soul!❤

[@Zen_Power]

Sun: Charged particle attack!!! Earth: magnetic field cloak!!! Mars: ….ah crap

[@BiserAngelov1]

I always thought, that we just switch up the pointer's names in the compasses. It looked like a simpler solution to the magnetic poles naming issue.

[@dunsel5887]

the needle on a compass is positive/negative, the Earth's magnetic poles are positive/negative, the north/south on a compass is to show the user the direction of north/south.

[@yahorholik4389]

Thank you for what you do

[@sparkyprojects]

The north end of a compass needle is south, so it will be attracted to the north pole. iirc, the right hand rule confirms this, the video 'Solenoid Basics Explained' shows this.

[@jwmmitch]

So south of the equator do compasses so point north, or flip and point south?

[@Warlord0302]

@StarTalk Dr Tyson, can you please explain Cold Fusion?

[@beammachine4525]

thank you for explaining. metal is heavier than stone so when earth was molten it fell towards the core. why did no one tell me that before. now i understand why metal is in core

[@stephenfrench3888]

Does anyone know of any videos where Neil gives his thoughts on the lights on proxima B ? That many claims out there it's hard to know

[@thenextplaygamer6228]

This guys a legend hes one of my favorite scientist his show cosmos was amazeing and he was also really good in universe and so much more

[@davekirk100]

I always thought that a compass needle was magnetised such that the pole of the needle which was labelled north was actually its south pole

[@KaceyGreen]

I thought this too

[@christopherfite994]

Favorite channel

[@itspunit01]

Chuck's expression killed it .. when NDGT said south magnetic pole is in North

[@ahmedatifabrar7698]

7:28 Dynamo's rotor magnetic poles are flipped? Isn't it the case for rotor of induction motor?

[@wrekced]

@Neil I believe that the Cambrian "explosion" of different forms of life happened when there was a big drop in the strength of the Earth's magnetic field. So the decreases in the magnetosphere that have happened in the past are not correlated to extinction events; but there does seem to be at least a bit of evidence that less magnetic field sheilding Earth from the Solar Wind can be a source of a higher rate of mutation in the lifeforms here. I wonder if anyone has looked into whether there are diversification events associated with magnetic field reversals and other drops in the strength of the Magnetosphere in the past.

[@gypsypunkparty]

Now this is an intriguing question!

[@enadegheeghaghe6369]

Interesting comment. I would just point out that in a majority of cases mutations are actually harmful to the organism. Lots of individuals have to die to allow the few with advantageous mutations to survive

[@user-tc1fw5ms5s]

"Pay what you owe Santa!" - i caught Chuck's quoting of Boondocks. That was a classic episode.

[@GR000]

So Dr Tyson, in saying that the Earth's South magnetic pole is in the geographic North, are you saying that there is an inherent property of "Northness" that is possessed by all compasses? Or wasn't the N pole of magnets just so named because of where they pointed? Would the N pole of the bar magnet still be so labeled if earth had no magnetic poles?

[@billbaker9623]

So how long does the it take for the magnetic field to flip and how long is at zero?

[@matthewjubb8080]

I love these so much

[@pjg6019]

Where are the magnetic poles during the time they're flipping? At mid point are the poles on the equator?

[@klaxoncow]

What Neil asked "which way does the compass point?", I totally shouted "South!" at the screen. :D (Although, yes, I should have correctly specified "magnetic South". It is correct to say North, if you mean geographic North.)

[@saschaschneider9157]

Maybe the compass needle is a magnetic southpole diguised as northpole and therefore earth magnetic north is real. It is all a matter of definition.

[@shanegallant9018]

Here's a curious question: I already knew about the fact that the north pole (and I assume the south pole) moves around a fair bit. What I would be curious about is how large of an area takes up the magnetic north pole? I'm guessing it's not a pin head area where if you stand directly over the 'pole' and move the compass around yourself, the compass's needle will constantly point at you until you give up and go home. But I have no idea how large the magnetic north pole area is! (And as an aside, I'm uneducatedly guessing that if one stands in that area, the needle would perhaps try to point straight down?)

[@chullotm1970]

If the last Magnetic Pole Reversal was about 780.000 y ago and these reversals happens about every 500.000 y, does it mean its due? Also, I read that a Magnetic Pole Reversal takes about 7000 y to complete, if so during this flippening the Earth will get more radiation from solar winds and cosmic radiation, does that mean that we would not survive? And finally, how long before a Magnetic Pole Reversal occurs can we predict when it will happen if we could at all?

[@kseyffert]

The South Pole is in the North. The logic is sound but seeing its a compass, could it not be that the pol Inter is not simply miss labeled so the South of the pointer agent is labeled North so it actually points North?

[@flyme2themoon720]

Can you do a video on the Tree 3 idea..Myke

[@esszee7426]

I hv always been confused coz my little spherical compass always points in the opposite direction of the North. I must get it checked now.

[@qwazse4]

Spherical compasses are designed to be read from the side. So the markings reflect the direction that you are looking.

[@ridetheapex]

I just thought they put the magnet in backwards. So the red part of the needle is actually the south of the tiny magnet under the red.

[@EG80]

When the polls flip, would someone in the equator be able to see an aurora or would this not happen because of how the magnetic field would change from north to south and south to north? Is it an instant flip with nothing being able to have the chance of physically moving to the equator or would the change take time?

[@madamnoire7464]

Can you please do a video on van allen belt.

[@HeartlessRingleader]

I loved the little Boondocks nod

[@jonnybgood1079]

If I were to build a compass and one needle pointed towards the North I would probably Mark that as North. My question is how do you tell what is north and south on a magnet?

[@dqixsoss7436]

It was arbitrarily decided at some point. Now tho you can do experiment to do with electric currents as they form magnetic fields so you can tell which end of a magnet is north that way

[@the5quatch]

It would seem you may have noticed my tweets? If so, thank you for reading my ideas there! If not, well that makes sense too. You are a busy guy. In that case, thank you for the very cool episode of Startalk that talks about everything surrounding the ideas I presented in a series of tweets to you. This could be very, very important information for many to understand, as it will likely play a key role in forecasting earthquakes. I will give a brief overview of what I am referring to here, for those interested. Anyone who has been through introductory physics, or even many general science courses, knows that you can induce physical changes in a magnet by affecting it's field, without ever touching it. Now, the Earth's field, as Neil describes very aptly in this episode, is generated by enormous currents of liquid metal in the core of our planet. These magma flows would likely effect the triggering of earthquakes if they change, especially suddenly. It is not a stretch to imagine flow distortions sending pressure waves against the inside of the mantle, like new ripples or flow changes in a stream or river when you change the flow of the water somehow. These would be ripples in billions of tons of liquid metal, so could interact with already tensioned fault zones by colliding with the inner mantle. But, how would one cause these ripples? Well, this is where our sun and the Northern and Southern lights come in. Auroral activity is caused by huge storms of charged particles colliding with our magnetic field, that is generated by this dynamo system inside the Earth. We are talking physically tons and tons of material colliding with and being redirected by our magnetic field alone. This would invariably cause distortions in the magnetic field. The larger and denser the cloud of charged particles from the sun redirected by our B field, the more it becomes distorted temporarily. Now, this must cause induced physical changes in the dynamo system in the core, similarly to when you use a piece of metal to drag a magnet across a table without touching it, but on a much larger scale, with billions of tons of liquid metal. This could potentially cause flow distortions within the dynamo system, ripples, to trigger earthquakes. Now, we have research that shows a correlation between CMEs, or coronal mass ejections (when the sun shoots a large cloud of charged particles at the Earth), and earthquakes, so it isnt far fetched to think this may be the physical causal connection between the two phenomena. So, to use this, it would seem that we could try to build a virtual model of the dynamo system using seismic data and magnetic field data to correctly model the shape of the solid core and roughly how the liquid metal flows are at some initial time. We would want to add as correct of a model of the mantle and crust to model the whole Earth. Then, we can shoot virtual CMEs of various sizes and from various angles at this virtual earth, and see how it causes ripples in our modeled dynamo system. This data could allow us to line up where these ripples collide with the modeled mantle, and allow us to attempt to forecast earthquakes and volcanic eruptions based on what we currently know about fault zones and different tensions they are under. If someone else doesnt get to this first, I will do my best to generate a model like this once my own situation has become more stable. I just wanted to share this set of ideas as freely as possible because of the level of importance to the whole Earth. Ideas like these are never really our own anyways, especially if they can potentially save lives or even entire cities. Most of the components of these ideas were other peoples as well, and I am sure I am not the only one considering this set of ideas because of this. If we ever see further than others, it is because we had the priveledge of standing on the shoulders of giants. Thank for reading my rambling here, if you did. If I can get a working model in Mathematica or Matlab sometime soon, I will share that freely as well. Again, ideas like this, that can save lives across the globe, they arent meant to be held hostage for credit, because they arent really all our own ever anyways. Thank you Neil again for this awesome video, and all the rest of your content, from Startalk to Cosmos and beyond. Carl would be so proud of everything you are doing sir, and I am as well. Every day, you bring more science to a world that so badly needs it. It will always be appreciated. ❤❤

[@blankenheim39]

A compass still does exactly what it is supposed to do, pointing out the north *direction* (which has the south magnetic pole). I don't think it was ever made to show where the north magnetic pole is.

[@davidbrown2704]

You said, essentially, "since the north side of the magnet points north, then the north pole must be the south magnetic field". But couldn't it also just be that the part of the compass' needle that says "north" is really the south end of the magnet? Why are we confident that it's the Earth's magnetic poles that are flipped rather than someone just labeling the opposite sides of a magnet?

[@alexmitchell2622]

As a young kid I realized a compass North pin is negatively charged because I used a magnet on it. Pretty simple tbh

[@davidvanwell2071]

I would love to see the aurora borealis in Canada, however I have to cross the border first. I might stop in upstate New York first to get some Steamed Hams, first.

[@johngavin1175]

It's saddening that I had to scroll this far for a Simpsons reference

[@TheLofiSP]

This was a clip from one of their podcasts

[@Soldierblue211]

Disappointed you didn't include magnetic declination in this explainer and the variation that happens over time and that it's included on the back of maps so you can correct for it to get true north!

[@GentlesirGibbles]

How have earth dynamo models changed since the observance of 2 cores? Or is that theory?

[@nigeljordan]

Reminds me of True North, Grid North, Magnetic North and using a declination diagram to calculate the degree difference between each 😅

[@ra2186]

I have to do this when I fly. Otherwise I'd end up in the wrong state.

[@AceSpadeThePikachu]

Just gonna add a little correction about Mars here. Recent data from the Insight lander indicates that Mars's core is indeed still hot, molten and iron-rich, but is much more diffuse than Earth's core. So now the leading hypothesis is that Mars's core became too saturated with sulfur compounds and other non-conductive materials to carry an electric current.

[@ariannanorris-landry4428]

So that's why Elon is in such a hurry to get to Mars. He's going to bring some really big jumper cables and get Mars started up again or something else just as delusional.

[@AceSpadeThePikachu]

@@ariannanorris-landry4428 I imagine he's probably a big fan of the movie "The Core."

[@stephaniewilley727]

Neil, aren't the North and South magnetic pole designations simply arbitrary assignments? and as such aren't the north pointing needle of my compass in fact a south pole that is simply painted with a little 'N" ?

[@allenwhite7725]

Boondocks references is just not something I expected from my explainers 😂

[@BugattiModzz]

Coulda sworn i saw this year's ago on this very channel

[@5ebliminal]

Come up to kuujjuaq quebec one day! The northern lights show towards the end of summer!

[@greywolf3457]

Nice Boondocks reference Chuck

[@kothakim]

Love you sir!

[@greenandgold2185]

Just don't have anything plugged in when it happens right? What would it do to our power grid?

[@durragas4671]

You know how Neil said that iron is in the middle because it's heavy... but at the centre of the earth gravity ends up being zero because the mass of the planet pulls in all directions equally. So like the eye of a storm there should be zero G right in the middle.

[@beammachine4525]

well. yes gravity might be zero in the ecact centre. but mass will be very dense from the gravity around the core pushing things towards the centre

[@limassolspearfishing7847]

So what was named first the poles of the earth or the poles of the magnet?

[@chandantiwari171]

Please make a explainer video of Bose-Einstein condensate

[@firemedic23-5]

Dr Tyson, in one of the Pirates of the Caribbean movies they talk about a green flash at sunset, is that a real thing, and if it is could you explain it. Thanks in advance

[@enadegheeghaghe6369]

If you are wondering if people return from the land of the dead with a green flash the answer is no. LOL

[@scottnelson1713]

That Einstein basketball example was from The Far Side.

[@Kelly_t_love]

Love chucks boondocks reference haha 😄

[@mods1133]

So, what kind of reaction to the earth occurs when the magnetic poles flip?

[@diablo4x4]

Thanks!

[@hometownhero334]

You going to pay what you owe Santa 💀😂💀😂 chuck with the boondocks reference

[@morlin101]

And also I have something else to say we think so much about ai and scientific experimentation but we forget that we have created a quantum ai and we forget that when you try to measure something in the quantum it goes from being in a superposition to having to choose one or the other that being said you have to have faith Neil and what's in the middle of faith AI

[@MrRlisis]

Is a magnet kind of a perpetual machine in itself, perpetually attracting or repelling?

[@DW-nx4dl]

No as it will stabilise at some point and fix in 1 direction