Neil deGrasse Tyson Explains the Edge of the Earth

Where does the Earth end? On this explainer, Neil deGrasse Tyson and comic co-host Chuck Nice explore the Karman Line, where Earth ends and where the great expanse of space starts. Does Earth have an edge?
How do we measure the extent of gaseous objects? We take a deep dive into measurement precision and the Karman Line. How high up does the atmosphere go? What is the diameter of the sun? We break down different ways we could choose to measure Earth’s atmosphere. And does Earth’s atmosphere really extend 100km out?
Get the NEW Cosmic Queries book (5/5 ⭐s on Amazon!): amzn.to/3dYIEQF
Support us on Patreon: / startalkradio
FOLLOW or SUBSCRIBE to StarTalk:
Twitter: / startalkradio
Facebook: / startalk
Instagram: / startalk
About StarTalk:
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!
#StarTalk #NeildeGrasseTyson

[@michael-4k4000]

Chuck is the type of comedian you just look at and laugh, knowing he’s thinking about something funny all the time. Also like how he’s always funny with out making fun of someone or some thing. Chuck is one talented dude!

[@NoalFarstrider]

Hearing Neil talk about science calms me down so much. Being reminded "to keep looking up" always puts my little problems in perspective. It reminds me of the gravestone epitaph, "I was once like you. One day, you will be like me." We have but a blink of the cosmos eye to live and die, and it matters to none other than me. NoalFarstrider.

[@sapelesteve]

Yet another excellent discussion of a very interesting topic Neil & Chuck! You have clarified a subject that I had always wondered about! Always look forward to your videos! Thanks for educating all of us Neil!

[@quillanthrasher6846]

Yo I love you guys I really do! Thank you so very much to the both of you for taking your time just to talk about something different I can really fall into. I love the back and forth and the facts and jokes, just all of it. I watch as often as I can and you guys never let me down, thanks again

[@StarTalk]

Education is our mission. Thank YOU for this lovely comment.

[@FacesintheStone]

I really enjoy this channel as well. It’s one of my mains :)

[@neptune7836]

@@StarTalk and educate y'all do 👏 👏 👏

[@gustavoabanto3486]

!8;

[@sethjackson9718]

@@StarTalk wish this is how high school was taught 😂

[@gretchencollier5122]

I love Mr Tyson's way of explaining things!!! He takes difficult concepts and breaks them down so that even children can follow him without ever making anyone feel less intelligent in any way. It is a true gift. I love him

[@Jacob-xe2si]

I love how Neil says, “I can think of ten other ways you might define it” when talking about the Carmen line. I’d sit here and listen to all of them. Super interesting.

[@hiimgamerspruzzino5804]

Ngl Mr. Tyson is the person who's gettig me really interested in studying physics after a bad experience with it in high school. And you Chuck, you make things even more fun. It's just so good to make videos both entertaining AND instructional, just so nice

[@Jackmerius_Tacktheritrix5733]

I'd prefer if you lied.

[@maple_vanilla]

I'm 18 and looking into studying physics too. Its just fun to me to have a challenge to work on and think about every day.

[@mcrowl2823]

Now we need a episode on the 10 ways Neil can define the boundaries of space.

[@colorsnstuff9465]

I watch so many of these videos I believe I’m starting to sync up with you guys… just this week I was trying to google how high the atmosphere went and it left me wondering why it was such an even number! You guys never disappoint to deliver the most important facts I didn’t know I needed 😁❤️

[@martinusamsterdam7667]

Love this channel, it's informative and hilarious at the same time. Best wishes for 2022. Greetings from Amsterdam, the Netherlands

[@shaidrim]

Well, measure units themselves are something we agreed on. That’s also how we shape reality with our mind.

[@aliasiq]

love the StarTalk logo on chucks tv in the background... real slick

[@RhapsodicXStyle07]

I remember seeing an article where researchers found the atmosphere extending well pass the moon, we are talking about few molecules per meter of various gases that are still gravitational bound to Earth here.

[@johndavidwolf4239]

At some point between the Earth and the moon, whatever molecules that exist switch from being in earth's atmosphere, to the moon's.

[@imatop10]

If you want to be really precise the universe has an atmosphere. Outerspace is not totally absent of gas molecules. Neal has actually discussed this in a past video.

[@sandal_thong8631]

I remember hearing that one too: that Earth's gases float past the moon. Maybe when Earth is between the moon and sun.

[@Ban00]

@@imatop10 can you link it pls

[@imatop10]

@@Ban00 kzbin.info/www/bejne/p3aalYyepa6SmKs

[@waterashwagandha3]

i was just wondering this yesterday & i just came upon it... thank you for answering my question Dr. Tyson & Chuck

[@J.D.Mc.]

I love this channel. Its my daily dose of food for thought. Thanks guys!

[@debbiehoagland548]

Chuck HILARIOUS as always! Very interesting topic! Keep posting these awesome videos

[@richardking1]

Neil & Chuck makes such a great combination to learn astrophysics from

[@suchithsridhar8460]

Another important thing about measurements... What is the purpose of the measurement? If you want to see if the table fits in your room then a ruler will do :). Doesn't have to be more accurate or precise than it needs to be.

[@hatezis]

word up for mentioning Kármán, a fan from Hungary

[@StarTalk]

Hello there! Thank you for being a fan of the channel :)

[@tuomassaarinen]

Everytime I see Neil Degrasse Tyson, I think about what an influence he has been. Science ambrassador.

[@mukamuka0]

3:44 You CAN'T hold your breath if the airplane lost pressure at high attitude. The suddenly change in pressure is so much that the air will be forces out of your lung. That why you'll lose consciousness real fast with in 10-15 sec not 1 min.

[@jazziespaz]

Love that space groove you play at the end of your talks. Needs to hear more! Totally Funky!

[@linkthehero8431]

2:26 "I believe you measure that in how bad it smells" "Not all gas came out of yo rear end" 🤣

[@larrycave5971]

Hey Mr.Tyson & Mr.nice just wanted to say i love your videos y'all are hilarious together. I have learned so much more than I thought i would from your videos. I've always loved science and learning about the universe

[@McDILLIGAF77]

Awesome, thank you Neil and Chuck!!!! As always, great discussion

[@franks1875]

Very interesting. Thanks! How about the speed of a spacecraft? What is it relative to? That would be an interesting Star talk discussion.

[@ngnatural]

Chuck, your comedic timing is just as on point as Neil's facts. Not easy to do!! Great stuff as always guys!

[@MarkLoveJoy88]

Thanks for all the great videos

[@JohnSmith-ie1tu]

One of the best bromances ever. Keep up the good work guys.

[@Apollorion]

I thought that that Karmen line was defined by the height where the (circular) orbital speed is equal to the speed of molecules due to their temperature. Does this accidentaly agree with the more sensible that definition Neil described in this video or are these two definitions of the border between outer space and the atmosphere due to some physical processes equal?

[@soulbound11]

Really interesting happenstance, the youtube channel Adam Savage's Tested just released a video today where Adam is also talking about measurement philosophy and how you cant truly measure something. Its a bit ... long, but gets a lot more detailed with explaining and walking you along to the understanding of it. Funny seeing both these videos on my subscription feed in the same day, lol.

[@illuddivinus3309]

This is definitely Neils most passionate topic. Probably the one with the most videos.

[@markbathe5649]

Chuck you bring a whole different aspect to the learning of this science I think can change stuff

[@XxTheAwokenOnexX]

Happy New Year Startalk

[@christianholmes8019]

This is an amazing explainer on the relativity of perception!

[@Yaroslav_Tselovanskyi]

these 15 min ones are the best, if you could make them longer but of the same format (no guests).

[@mururoa7024]

As every woodworker knows, everything measures either 3/8, 1/4 or 1/2 inch. So the universe has to be one of those three. 😉👍🏆

[@chriswright3216]

This is by far one of the best ideas ever to science and comedy aspect together but I only think it could work with certain people in these two knock it out the park for sure

[@timknight5105]

Super interesting! Thank you!

[@Lanhoj]

*That's gotta be a fun party...* 12:49 🥳🎉

[@MukeshPanicker]

I wondered about this since childhood !! Thanks so much for the education.

[@murasaki848]

4:30 Reminds me of a lyric from the song Lullaby by Tim Minchin - "One thing they don't mention in the parenting book: Your love for them grows the closer to dead they look..."

[@dongiles]

Neil, I get the overall point of this episode but in your first description of the Karman line you said it was the point where the sky was no longer blue but black. I was stationed at Beale AFB in the 70s and know from talking to SR71 pilots that at 85,000 feet the sky is black during the day and you can see an amazing amount of stars. 85,000 feet is well below the Karman line.

[@DaT0nkee]

Interesting definition of the Kármán line. So far i thougth it is defined by aerodinamics, and plane flying capabilities.

[@rookangelofmercy7283]

Every chuck video is a watch!

[@UHFStation1]

Chuck learns something new every time.

[@davegrox3150]

love yall videos but could you make the audio a bit louder? thanks!

[@V1RU5420]

how much effect have solar winds on the this? so is it thicker on the sides of earth pointing towards and away from the sun? how does the rotation effect it? and whats with the poles wich do not rotate away from it?

[@BabyCee713]

I love the mix of scientific facts & jokes!!!! PERFECT 👏🏾👏🏾👏🏾

[@plasmaburndeath]

Another question is "When was the diameter of the Sun Measured?" It is slowly expanding as it consumes its fuel.

[@preeti3624]

Chuck!!! I sync with Neil automatically at the beginning of each video. ;)

[@glenncastro1922]

I thought I was the only one that did that! 🤣🤣🤣

[@kizzmitten1]

awesome stuff, thank you!

[@brettelm115]

Please don’t stop making these

[@MrDelta144]

Never cease to blow my mind Neil!

[@danielludlow8960]

Oh my god!!! Chuck looked so confused when you explained the Carmen line.

[@culturefan]

My friend and I were talking about outer space (I forget the context), but he was talking about going at light speed or something like that, I questioned what about bumping into something (meaning a planet or asteroid, etc.), and he said, "How? There's nothing out there." Which I'm guessing he meant once you get outside our Milky Way. Can you talk some about this or the vastness of space?

[@philipberthiaume2314]

If you could drive in an upward direction in your car, at 100km/hr which is the speed limits on most Canadian highways for example, it would take you only one hour to get into space from sea level.

[@philipberthiaume2314]

@@cosmic_love_5 lol, you mean 17th century knotted rope measurement units?

[@johndavidwolf4239]

@@cosmic_love_5 9.26 E-9 c

[@johndavidwolf4239]

@@cosmic_love_5 : "c" is the speed of light in the cosmos you love, the velocity that only requires one unit to quantify, the unit that is "free" of any arbitrary 'man made' standards.

[@johndavidwolf4239]

@@cosmic_love_5 Just multiply the number I posted by the speed of light in MPH, or just use 61.

[@SwagMarathi]

Thank you❤ from bottom of my heart

[@RedNoseGETEM]

Yes!! We need to hear how does it get colder the closer we get to the Sun?!?! Before it starts getting " hot" of course.

[@imatop10]

Your discussion is in line with #Adam Savage’s Tested video published yesterday. The title is 'Adam Savage's Epiphany on the Science of Measurement!' Great discussion regarding this topic.

[@Bad_Wolf_Media]

If anyone at StarTalk sees this, please recommend to Neil that he he checks out Adam Savage's video on his Tested channel posted today. Because he delved into this same discussion (talking about accuracy of measuring). It was a pretty great perspective.

[@Hotlux66_]

I want to see Neil in space, giving us a startalk from up there

[@KRONOSNCC1701A]

Excuse me Mr.tyson could you do a video about the colonization of planets like Mars or the moon I would love to hear what you think about mr. Musk and his visions

[@jasonremy1627]

Adam Savage just dropped a video on measurement very much like the first bit to this. It's very good.

[@kevinallen1699]

Please do a show on Thunder, Lightning and the correlation of the two.

[@JTStonne]

I love your show. Can you explain why the atmosphere doesn't get pulled out into space? I've been told that if two boxes were connected with a sliding door between them. One has 1 atmosphere of pressure and the other is a vacuum, when door is opened the air fills the vacuum to equal out the pressure.

[@johndavidwolf4239]

There two schools of thought: One is gravity, the other is the earth sucks.

[@TyBeTroLLing]

Because the earth is flat

[@ExtremePacifist]

Where does the Earth’s spinning atmosphere stop, and the vacuum of space begin? At the Karman Line? Between the Exosphere and Thermosphere? Not all scientists agree that the exosphere is really a part of the atmosphere. Some scientists consider the thermosphere the uppermost part of Earth's atmosphere, and think that the exosphere is really just part of space. However, other scientists do consider the exosphere part of our planet's atmosphere. How is the atmosphere, which is a gas, and the Earth which is a solid, and the water, which is a liquid, all moving at the same speed as one body? And if the atmosphere is a gas, how is it different from other gases like wind from hurricanes or simple directional breezes? Inertia is the term that describes why we don’t sense the movement. But using the train or plane analogy, we must take into account the physical barrier, steel, aluminum, glass, etc...that prevents the resistance force to be felt. Roll down the window of your car and those forces will be felt. That leads to my question: at what point in the upper atmosphere does this invisible protective barrier exist? The exosphere or thermosphere or the Kármán line.

[@nickylocks]

Looks like Chuck is wearing a Black Lantern shirt!!! Is he secretly a Green Lantern fan? Love the show and you guys!!!

[@nevarran]

Chuck "It's like measuring with hands..." Me "Foot? Hello?"

[@RashidJafarpoor]

You guys are one of the best duets in history ❤️❤️

[@azzammeeralam7182]

I’d like ask what prevents air from escaping our atmosphere to outer space?

[@r.slaurent437]

Long story short, gravity

[@johndavidwolf4239]

@@r.slaurent437 : Either that or the Earth sucks.

[@sandal_thong8631]

Also, the magnetic field keeps the solar wind from blowing it off.

[@ExtremePacifist]

Where does the Earth’s spinning atmosphere stop, and the vacuum of space begin? At the Karman Line? Between the Exosphere and Thermosphere? Not all scientists agree that the exosphere is really a part of the atmosphere. Some scientists consider the thermosphere the uppermost part of Earth's atmosphere, and think that the exosphere is really just part of space. However, other scientists do consider the exosphere part of our planet's atmosphere. How is the atmosphere, which is a gas, and the Earth which is a solid, and the water, which is a liquid, all moving at the same speed as one body? And if the atmosphere is a gas, how is it different from other gases like wind from hurricanes or simple directional breezes? Inertia is the term that describes why we don’t sense the movement. But using the train or plane analogy, we must take into account the physical barrier, steel, aluminum, glass, etc...that prevents the resistance force to be felt. Roll down the window of your car and those forces will be felt. That leads to my question: at what point in the upper atmosphere does this invisible protective barrier exist? The exosphere or thermosphere or the Kármán line.

[@Chaicowski]

If Niel and Tyson stopped discussing physics, would it ever be fun to learn about again?

[@evilpandakillabzonattkoccu4879]

@0:56 or so: Interesting thing we did while I was framing houses; since the cuts have to be as exact as possible, but a tape measure uses 1/16th of an inch increments. So, what happens if you're between 4' 11 and 15/16" and 5' even? our solution: we split that 64th of an inch into 3rds. If the measurement was directly in the middle, we would say "4ft, and halway between15/16ths and 5ft" (simple enough, but exactly in the middle...that's rare). If it's less than halfway the two, it's "4ft, 11 and 15/16ths *weak*" .....if it was more than halfway, it was "*strong*". So, with increments of 1/16th of an inch, "strong and weak" allowed us to estimate down to 1/32th of an inch. That was our solution. wasn't perfect, obviously.

[@SettaXY]

I wish this didn't end. Got me thinking out all types of stuff

[@paulosfajardo]

The Blackest Night falls from the skies The darkness grows as all light dies We crave you hearts and your demise By my black hand, the dead shall rise! Awesome shirt, Chuck!

[@lorettawatkins5024]

I know this is off topic, but what is that gorgeous column over Neil see right shoulder???

[@joanfregapane8683]

Another great video.

[@ExtremePacifist]

as for the plane analogy, and inertia, the plane is encapsulated, literally surrounded and shielded by real physical protective barriers, like aluminum and other materials. our planet has no such protective pysical barriers, as the scientific community seem to agree there’s no sudden transition from atmosphere to space. Rather, there’s a gradual thinning of the atmosphere across five layers, so the Karman line is not a pysical barrier, so we are back at the original unsolved mystery; how can the atmosphere rotate , unobserved and unfelt, while all other forms of gas and air move freely in all directions?

[@sandal_thong8631]

A video I recently saw talked about sunspots and solar flares or the lack thereof causing the atmosphere to rise and satellites having to increase their altitude to avoid atmospheric drag. Just as they say that 100 km is arbitrary, so too is the altitude above atmospheric drag, maybe 1000 km.

[@PajakTheBlind]

13:26 except it almost is :D look up the Metre Convention - USofA is a member state. 13:53 except Gagarin was earlier and Vostok 1 went higher ;)

[@umbragladium]

Soooo, reading the thumbnail I actually thought we were talking about something closer to the origins of The Big bang. Still enjoyed the video lol

[@PerfectPetProductions]

Neil's an extrovert, he interrupts all the time and other charges have no foundation. Still watching every video

[@ujjwalbhattarai8670]

When I feel bored. I just come to see video. It's really funny, I laughed and removed all bored. It's really funny like Charlie Chaplin and mr bean. Great.

[@Chaicowski]

I think a black hole is where a universe starts/end. Hence why light doesn't come out, (reflected) becuase its continues onward. Otherwise space is traveling faster than light. That only happens at the edge of our universe, therefore a balck hole could be a tear in space where matter/energy leaves and becuase we are a "higher pressure" universe, only pure energy makes it out. Just an idea I'm not fully committed to it.

[@blackpanther6389]

A dude named Nassim Haramein has published papers based on concepts that sound very similar to your idea. He's got some weird conspiracy stuff out there, but his science stuff is quite interesting.

[@jettmthebluedragon]

Or perhaps of a life cycle 😐a endless cycle of life and death perhaps 🙂

[@AceSpadeThePikachu]

If we really want to get technical, one could define the edge of Earth's atmosphere by the point at which in terms of density and composition it becomes indistinguishable from the interplanetary medium. Though for bodies that have no atmosphere, like The Moon, you'd have to use a metric that doesn't involve gas density at all, like the gravity well.

[@TabernadoDani]

But I guess that is the whole point of the video, there is no such point where the atmosphere gets indistinguishable from the interplanetary medium. It would be more like an interval, a whole range where that point could be depending on all the dynamic factors like the molecules moving, etc, etc. How big would be the chunks to measure that density? (after all you need a volume), etc. So in the end it would still be an arbritary, not absolute definition. And you could go beyond, interstellar space is known to be less dense than interplanetary space, so are all the atmospheres in the solar system just sorta together? Where does each individual atmosphere end, is there a solar system atmosphere? Lol, I'm just teasing now :) but what I mean is that even if we go with very logical definitions, in the end it will still be an interval/idea rather than an exact point. There are no exact points

[@RickySTT]

Is Neil trying to justify Richard Branson not making the Karman Line?

[@Chemy.]

this should be on schools

[@RashadShort]

Can we just take a moment and appreciate the fact Lord Nice is wearing a Black Lantern shirt. 👏🏾👏🏾👏🏾👏🏾👏🏾

[@blackparadoxx9656]

This explains why nobody can agree on the true size of Uranus.

[@abedt1702]

Chucks banter is actually on another level 😂

[@tootsweet4us]

I am a HUGE fan - No matter what standard of measurement you use. I just want to know how many takes of this did you have to do before you got one without Chuck at least hinting at something naughty with regard to how should we measure something. 😜 Seriously though - Excellent talk, as usual. Love things that make us question our answers.

[@beebo236]

Hey Neil! I got a question! If there is a neutrino burst that is emitted during a nuclear explosion, and a neutrino burst so far away from a host star on a planet with low amounts of molecular reactions is rare in the universe, what are the odds that the Manhattan Project was a disco rave for the rest of the universe? And having said that, would the current uncertainty of the existence of extraterrestrials and the government's increasing willingness to discuss the topic mildly prove that first contact might have already been made?

[@DerekFullerWhoIsGovt]

8:27 How often and how far do they correct the orbit?

[@rickkwitkoski1976]

google it...

[@martehoudesheldt5885]

here is one for you to do a show on . why do comets/asteroids go around the sun instead of straight into it ? and why we have never seen it happen?

[@aaronbailey3942]

@StarTalk hey, is it possible that laws oh physics break down at a black hole because the math is using the base 10 system? Maybe if there was a different number system created.

[@basic6154]

ndt blows my mind always

[@BlazinPass]

Ahh yes. The question that keeps me up at night. lol

[@cincin0722]

I wonder who the first person was that realize space was a vacuum and how they found out

[@lucyspearl]

2:26 Chuck with the timely joke. 🤣🤣🤣

[@CRUZER1800]

it would help if you boosted your output volume.... can hardly hear you and Chuck.

[@cajunqueen5125]

This is the same problem as trying to measure the length of a country's coastline. You'll get different numbers, depending on what lens you want to use, how finely you want to zoom in and measure the details of all the ins-and-outs.