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Exploring the Universe: Crash Course Big History #2

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  • Опубліковано 23 вер 2014
  • In which John Green, Hank Green, and Emily Graslie teach you about what happened in the Universe after the big bang. They'll teach you about cosmic background radiation, how a bunch of hydrogen and helium turned into stars, formed galaxies, created heavy elements, and eventually created planets.
    For more information, visit www.bighistoryproject.com
    Crash Course is on Patreon! You can support us directly by signing up at / crashcourse
    Want to find Crash Course elsewhere on the internet?
    Facebook - / youtubecrashcourse
    Twitter - / thecrashcourse
    Instagram - / thecrashcourse
    CC Kids: / crashcoursekids

КОМЕНТАРІ • 2,3 тис.

  • @gyinagal
    @gyinagal 8 років тому +1277

    "Today we will be talking about what happened after the Big Bang."
    This is quite possibly the vaguest statement possible

    • @destoryeverything9677
      @destoryeverything9677 7 років тому +41

      that can be anything from 0.0001 secs after it to 1000000000000 trillion years in the future, no limits there

    • @ireallyhatemakingupnamesfo1758
      @ireallyhatemakingupnamesfo1758 7 років тому +5

      destory everything in fact there is "no edge"

    • @TheSassi14
      @TheSassi14 7 років тому +7

      gyinagal
      The "today we are talking about" part is rather specific, but else true

    • @raenab1029
      @raenab1029 7 років тому

      gyinagal lol

    • @LelouchKilluah
      @LelouchKilluah 6 років тому

      Great! :)

  • @armaansoni6906
    @armaansoni6906 5 років тому +171

    hank: "I love chemistry",
    John: "I hate chemistry"
    yep, they are brothers!

  • @jdsyke
    @jdsyke 8 років тому +577

    Crash Course Big History #2: Our Stars and the Fault in Them

  • @RukiaSailormoon
    @RukiaSailormoon 8 років тому +572

    "Because let's face it our species isn't gonna make it until the sun wipes us out" I love these guys, always so blunt

    • @queensaharaice7376
      @queensaharaice7376 8 років тому +5

      Well,sadly its true😞😢

    • @Fearofthemonster
      @Fearofthemonster 8 років тому +23

      There are at least a million years. Don't underestimate the technology. 300 years ago we were travelling on horseback.

    • @dylanscanlan1857
      @dylanscanlan1857 8 років тому +16

      +Fearofthemonster Exactly. Technology has advanced so much in the last 10 years, you can imagine what it will be like in the next million. Besides, what's going to wipe us out?

    • @christianeh8846
      @christianeh8846 8 років тому +21

      +Dylan Scanlan Ourselves, with pollution and global warming

    • @dylanscanlan1857
      @dylanscanlan1857 8 років тому +4

      +Christian Eh That will require adapting but I 100% do not believe that we will wipe our selves out. We have survived a lot worse and we have always adapted.

  • @khoboo
    @khoboo 10 років тому +449

    My mind went blank when he says that there are other universe with different physics.

    • @AnstonMusic
      @AnstonMusic 10 років тому +67

      *Could* be, that part is a bit speculative. (Other holes *might* exist in that block of cheese) I was almost a little worried that he stated that as a fact.

    • @khoboo
      @khoboo 10 років тому +56

      The limit of my knowledge don't permit me to further comment on this.

    • @asgerlakkenborg2435
      @asgerlakkenborg2435 10 років тому +19

      In advance, sorry for any misconceptions/flawed logic as I write this:
      Currently, IIRC, the theory of different universes is not accepted in the same way as gravity, i. e. it hasn't really been proven. It conflicts with another theory, which might also be viable, called super-symmetry.
      If memory serves, the multiverse theory would indicate that everything is random, and that we exist in this universe only because this particular one happened to behave in a certain manner. The other one, super-symmetry, apparently leans toward a higher being toying around with us (And before you get all atheist-hypocritical, this is actual science, not religious mumbo-jumbo).
      Neither has been proven or disproven.

    • @mattdombrowski8435
      @mattdombrowski8435 10 років тому +6

      Andy Flow he's getting two different kinds of multiverses mixed up, for the first part the incredible uniformity of our visible universe suggests that it continues that way for a considerable distance, and since the number of possible arrangements of atoms in a space the size of a planet is finite, there are bound to be interesting arrangements. the different laws of physics part is something that falls out of string theory. string theory requires 11 dimensions, which suggests that what we call the universe (both visible and invisible parts) are on the surface of a multidimensional shape that appears infinite from within. using the same principle of remarkably even constancy there are likely many such multidimensional shapes that contain other universes. there is no reason why they would have the same laws of physics inside them so they probably would be different.

    • @khoboo
      @khoboo 10 років тому +3

      All of you are giving me knowledganism. And it makes me think of what is the purpose of our struggle for survival. We are so goddamn small compared to it.

  • @FieldGamers
    @FieldGamers 10 років тому +62

    Crash Coarse is easily the best Channel on UA-cam. I really hope people learn and become educated from watching these videos. They explain things so well and put things into words and graphics that everyone can understand.

  • @arthur9078
    @arthur9078 8 років тому +100

    This was such a mind-blowing episode. Like... WOW, the universe is quite something!

    • @queensaharaice7376
      @queensaharaice7376 8 років тому +3

      True

    • @BrianHutzellMusic
      @BrianHutzellMusic 6 років тому +5

      It’s quite simple really! The universe is like a cheese. It is bigger than a grapefruit. My dog was formed in its belly. Easy, right?

    • @EZR725
      @EZR725 4 роки тому +1

      @@BrianHutzellMusicThis comment underrated as hell

  • @BluueBiru
    @BluueBiru 9 років тому +28

    I'm so happy to see John and Hank working together on a video series. You guys both rock!

  • @KaletheQuick
    @KaletheQuick 10 років тому +84

    A wild Emily appears!
    Emily uses science!
    It's super effective!

    • @alexhood2886
      @alexhood2886 6 років тому +3

      KaletheQuick Donald trump use nuclear weapons on himself. it super effective!

    • @animationspace8550
      @animationspace8550 5 років тому +1

      Oof!
      0 XP earned

  • @ThatCarterKid
    @ThatCarterKid 10 років тому +43

    Just seeing these 2 episodes I can conclude that this is probably the best series you have done yet! I love it! and I also love all of your other series'! Thankyou for taking the time to make these! If the information is still correct I hope to show these to my kids someday! Thanks CrashCourse!

  • @spelunkerd
    @spelunkerd 10 років тому +42

    I know it's more tricky to get three authors to contribute to one vid, but the end result is a lot greater than the sum. John, it's fantastic to see you dip a toe into the realm of science.

  • @binbintrashtin
    @binbintrashtin 9 років тому +23

    "Your right hand, made in the belly of a star. Your left arm, potentially made in the belly of different star"
    What... What am I?

  • @stumpthegreat
    @stumpthegreat 10 років тому +23

    In one of my astronomy classes, we discussed several situations in which the Earth would be doom. For example, the Millky Way/Andromeda collision, the moon eventually leaving Earth's gravitational pull (or being pulled back in, and crashing down). However generally these all took longer than the life of Sun. As such, we had an ever growing list of bad things that would happen "...but it's okay because the sun will blow up first."

  • @Moonbeam143
    @Moonbeam143 10 років тому +109

    We are the Universe. The Universe is in side of us. That's amazing.

    • @davidshi451
      @davidshi451 10 років тому +2

      I know right??!!

    • @DUES_EX
      @DUES_EX 10 років тому +4

      So if i were the universe, i just went inside everyone? ;p

    • @Moonbeam143
      @Moonbeam143 10 років тому +11

      Everybody is inside you, too. We're all in each other.

    • @DUES_EX
      @DUES_EX 10 років тому +3

      Thats so deep ;p maybe too deep for me

    • @Rumble-Tusk
      @Rumble-Tusk 10 років тому

      Jack Daniels TWSS

  • @dejureclaims8214
    @dejureclaims8214 10 років тому +9

    With these new videos, Crash Course has rekindled some of the inspirational frisson that I first experienced watching major documentaries like Cosmos, The Ascent of Man, Civilisation, and Attenborough's Life series. I think John and the gang have really created something special here, that draws attention away from the mundane to resurrect our muddied relationship with the infinite.

  • @Marrowhunter
    @Marrowhunter 10 років тому +5

    “We are a way for the cosmos to know itself.”

  • @PotatoBearRawr
    @PotatoBearRawr 10 років тому +11

    Should have a warning: May cause violent nergasm.
    My brain is still syncing from all the awesomeness... MAKE MORE! Please :)

    • @davidshi451
      @davidshi451 10 років тому

      Spread the word, share these videos, and also check out Subbable!

  • @crashcourse
    @crashcourse  10 років тому +164

    In which John Green, *****, and Emily Graslie teach you about what happened in the Universe after the big bang. They'll teach you about cosmic background radiation, how a bunch of hydrogen and helium turned into stars, formed galaxies, created heavy elements, and eventually created planets.
    For more information, visit www.bighistoryproject.com

    • @NickHornetRuppert
      @NickHornetRuppert 10 років тому +2

      First.
      (GREAT VIDEO! dang. Better and better every time.)

    • @NickHornetRuppert
      @NickHornetRuppert 10 років тому +3

      Well, Matter isn't created nor destroyed. Just changed or transformed. I can see how millions of years later life was made from the elements that came from stars to make us millions of more years later.

    • @ThesilverbacknewsBlogspotwooo
      @ThesilverbacknewsBlogspotwooo 10 років тому +2

      I love your videos, man.

    • @snb14
      @snb14 10 років тому +10

      Correction note. The pop-up note at 5:42 incorrectly states the Laniakea supercluster is only 500 lightyears across instead of 500 million

    • @CarolinaMartinez-uv4tq
      @CarolinaMartinez-uv4tq 10 років тому +2

      Thank you for sharing so concisely and succinctly this knowledge. Love all the videos.

  • @senikaarce8897
    @senikaarce8897 4 роки тому +5

    You cannot convince me we’re the only life in the universe...it’s HUGE

  • @karanvirsingh7829
    @karanvirsingh7829 9 років тому +45

    0:49 "World War III will be fought by Radiant and Dire" subtle, Crash Course. Real subtle.

    • @VarunKini
      @VarunKini 9 років тому +1

      Karan Vir Singh Hahaha! It will solve so many problems with so little causalities.

    • @nonamed56
      @nonamed56 8 років тому +2

      +Karan Vir Singh i don't get it. you mind explaining it to me please?

    • @karanvirsingh7829
      @karanvirsingh7829 8 років тому +2

      Radiant and Dire. The two teams in DotA 2. (If you don't know what DotA 2 is, please Google.)

    • @nonamed56
      @nonamed56 8 років тому +2

      don't worry google is my friend. btw you are fast :)

  • @Altorin
    @Altorin 10 років тому +12

    I vote "Cosmic Latte" as a new Crayola color

  • @nilesrock024
    @nilesrock024 10 років тому +170

    There are people out there who don't like chemistry?
    You poor bastards...

    • @emperorpalpatine9841
      @emperorpalpatine9841 10 років тому +12

      Theres people who dont like anything. Deal with it.

    • @verdiss7487
      @verdiss7487 10 років тому +1

      I love chemistry, but I can't stand chemists.

    • @nilesrock024
      @nilesrock024 10 років тому +1

      Verdiss That's fieldist!

    • @nilesrock024
      @nilesrock024 10 років тому

      Emperor Palpatine Deal with what?
      How much it must suck for other people not to like chemistry, one of the most important and interesting fields at our disposal?
      Cause, I mean, don't think I actually have to deal with anything there...

    • @bacawaka2813
      @bacawaka2813 10 років тому +9

      meh. Chemistry is just applied physics.

  • @TobiBaronski
    @TobiBaronski 9 років тому +15

    "Your brain has more connections than there are stars in the galaxy." AAAAAAAAAAAAAAAAAAAUUUUUGGGGGGHHHHHHHHHHHHHH

  • @RandomGuy1235
    @RandomGuy1235 10 років тому +7

    This series is just to perfect. It combines the best of Hank and the best of John. Science, humanity, youtube, love and curiosity. I can't wait to see more of this historical science opera spanning the everything and beyond.
    Amazing work guys. This last half hour I was brought on a journey where I was awed and humbled, became proud to be alive and became proud of my species.
    Also, I don't know who Emily is but I like her. I don't know if it's the plan to alternate different people or just do all of this with you three, but I'm happy either way.
    Good luck guys! Can't wait for more.

    • @CanadianRM4
      @CanadianRM4 10 років тому

      She hosts a channel called "brainscoop". Check it out, it's pretty cool. She's also a taxidermist and shows how she skins and dissect dead animals. If you're sensitive to that stuff, then you probably shouldn't watch it or just prepare yourself.

    • @markruffruffalo9923
      @markruffruffalo9923 9 років тому +1

      She's the host of the Brain scoop on youtube check her out it's great

  • @theravendork5914
    @theravendork5914 10 років тому +10

    I. Love. This. Series.
    DFTBA

    • @davidshi451
      @davidshi451 10 років тому +3

      Share it with everyone you know!

  • @azavala5
    @azavala5 10 років тому +36

    The Mongols are made of stars too!!!

    • @SeraphimKnight
      @SeraphimKnight 10 років тому +18

      THEY'RE THE EXCEP- wait no

    • @TheKeksadler
      @TheKeksadler 10 років тому +5

      Mongol Exc- not this time.

    • @asgerlakkenborg2435
      @asgerlakkenborg2435 10 років тому +4

      Jeremiah B Everyone knows Temujin's balls were actually tiny stars.

    • @alannar.8701
      @alannar.8701 10 років тому +2

      Jeremiah B I feel like there's a Fault in Our Stars reference to make there, but I can't find it.

    • @AlpacasForAva
      @AlpacasForAva 10 років тому +1

      No they are the exception, learn their place. They were made by aliens not stars.

  • @TabithaUjang
    @TabithaUjang 10 років тому +13

    I feel so small after watching this video..
    *hi, I'm just debris, floating by*

  • @ragnkja
    @ragnkja 9 років тому +31

    M87 is called that because it was the 87th fuzzy thing Messier wrote down that he'd checked out in the sky while searching for comets.

    • @milomineon2787
      @milomineon2787 9 років тому +3

      I don't know why I laughed so hard at that XD

  • @LordMarcus
    @LordMarcus 10 років тому +20

    If we become capable of colonizing the galaxy, I am unsure why we would remain on our own little island, as you put it, John.

    • @theguy9208
      @theguy9208 10 років тому +8

      i imagine for the same reason the romans couldn't conquer the whole planet.
      its nearly impossible to govern a place that is years travel time away, and since nothing can go faster than light, we are very much restricted to living within our solar system and without risking the creation of a potential rival or enemy out of a colony light years away.

    • @hilsanka6621
      @hilsanka6621 10 років тому +11

      Because of the massive distance between even neighbouring galaxies

    • @LordMarcus
      @LordMarcus 10 років тому +1

      You both seem to have missed the functional part of the statement, "become capable of colonizing the galaxy." It's already given in this postulate that we can do that -- so, why WOULDN'T we do that?

    • @Meeko1010100112
      @Meeko1010100112 10 років тому +1

      We wouldn't because it is dangerous out there. The wild Wild West was wild, and it was even connected to the less dangerous eastern seaboard. Now imagine living in the new one, only so far away that light takes minutes to get from place to place. Even years, at a scale most would dream of happening.

    • @sabbywins
      @sabbywins 10 років тому +10

      He means we wouldn't leave our galaxy, not our planet. To be able to travel interstellar space within our own galaxy is one thing; but to be able to travel between separate galaxies is another problem entirely. At that point, distances become so big that there isn't any point thinking about them because we are unable to comprehend just how vast those spaces are. Besides, by the time we had thoroughly explored every inch of the milky way, it's entirely possible the universe will begin to die.

  • @MaryJane-bo6lj
    @MaryJane-bo6lj 8 років тому +17

    *VIDEO ERROR*
    4:05 milky way is 100,000 light years across
    5:43 Laniakea is only 500 Light years across!
    Oh wait, I forgot that space and time was held in place by a Tardis...

    • @koyx
      @koyx 8 років тому +2

      +Mary Jane Hahaha, I looked it up on and it's approxiamately 520 million light years ago, I guess they forgot the million.

    • @queensaharaice7376
      @queensaharaice7376 8 років тому +2

      A fellow whovian!🙌🙋

    • @TheMitchy27
      @TheMitchy27 7 років тому

      Mary Jane milky way is 110 million LY and laniakea is 500 million LY

  • @john.ellmaker
    @john.ellmaker 8 років тому +10

    Love these guys, just an update from Harvard Smithsonian though, newer research shows that heavy element production is likely to have come from neutron star collisions. While heavy elements are produced in the r process it doesn't seem to account for the relative abundance of heavy elements, but add in occasional collisions which produce extreme amounts in comparison and you have a plausible explanation. Even more recent research in 2015 corroborates this idea as isotopes on earth have been confirmed to come from a neutron star merger (Nature Physics)

  • @BudCharlesUnderVlogs
    @BudCharlesUnderVlogs 10 років тому +2

    This series is so awesome!

  • @FROPDESAI
    @FROPDESAI 9 років тому +35

    I bet that the 237 people who disliked this video are from North Dakota!

  • @er1nyes_
    @er1nyes_ 10 років тому +6

    School headmasters around the world, this is interdisciplinarity done right. Take some notes!

  • @Gigas0101
    @Gigas0101 10 років тому +1

    Thank you very much for the Carl Sagan quote! Great episode!

  • @justjollyjacob
    @justjollyjacob 10 років тому +1

    I love the growing collaboration.
    Which seems wonderfully appropriate, given the subject.

  • @godzilla964
    @godzilla964 8 років тому +142

    Since we are technically made of recycled elements, Reincarnation sounds like a more realistic explanation to what happens after we die.

    • @TIMEtoRIDE900
      @TIMEtoRIDE900 8 років тому

      +godzilla964 Reincarnation still requires some kind of waiting period, a place to wait, and "Angels" to shuttle your spirit to and fro.

    • @godzilla964
      @godzilla964 8 років тому +11

      +TIMEtoRIDE900 I don't think so.

    • @TIMEtoRIDE900
      @TIMEtoRIDE900 8 років тому

      godzilla964
      The day of the Tsunami 250,000 people died, and since the same ## weren't born, well, there's your waiting period.
      To not have "Spiritual Assistants" would mean that YOU are completely in control and responsible for the whole reincarnation process, that you would know exactly what to do and where to go.
      Your thoughts ??

    • @godzilla964
      @godzilla964 8 років тому +14

      +TIMEtoRIDE900 I look at reincarnation the same way I look at anything written by H.P Lovecraft. A force beyond any human understanding.

    • @TIMEtoRIDE900
      @TIMEtoRIDE900 8 років тому +1

      Fair enough.

  • @mattiestyles2020
    @mattiestyles2020 9 років тому +18

    If we come from dead stars, and if we still see the light from stars that have already died millions of years ago, is it possible that when we look up in the sky we are seeing the light from stars that made the atoms we consist of? Or, if they have been dead for so long, and we are still seeing their light, are these stars too far away to possibly have formed the elements that are on earth today?

    • @raph96.37
      @raph96.37 9 років тому +16

      Light travels faster than matter so...no

    • @samguy7654
      @samguy7654 6 років тому

      Mattie Styles That's so poetic Mattie.

    • @maxsteele3686
      @maxsteele3686 5 років тому

      The stars that we can see in Earths sky are approximately within 100 light years, the number of stars we can see is something like 0.1% of our galaxy.

  • @ALRuble
    @ALRuble 10 років тому +1

    John and Hank have complementary tempi and cadences of speech. It's interesting.

  • @edgeldine3499
    @edgeldine3499 10 років тому +4

    im from North Dakota... im just glad it was mentioned lol :D

    • @edgeldine3499
      @edgeldine3499 10 років тому

      also if you hover over my name you get to see the wonderful land that is my home ;)

  • @SenorJC
    @SenorJC 10 років тому +13

    Yes another crash course video!

  • @damascus21
    @damascus21 10 років тому +4

    11:57 Yay, it's Emily! I love Emily
    (Hank, John, you guys are great, too, but I love Emily)

  • @isabellag3490
    @isabellag3490 5 років тому +2

    John: *talks about the Big Bang and that we come from stars*
    me: *immediately goes to comments and stops listening to video but keeps it playing because I have to for school*

  • @grexwtf
    @grexwtf 9 років тому

    I like the cutting to different people to describe another part of the subject. Makes the pace of the program that much better. More of this format, please. You guys are doing great.

  • @HPDM14
    @HPDM14 10 років тому +3

    All these deep scientific and philosophical questions! I really shouldn't have watched this before going to bed, now I am going to have nightmares about the sun exploding!

    • @Zerepzerreitug
      @Zerepzerreitug 10 років тому

      I happen to know a piece of knowledge that may make your restless nights a bit more... restless:
      Imagine a hydrogen atomic bomb (the most powerful kind of bomb we've ever made) and holding it against your face. The explosion from that bomb at that distance would feel _weaker_ than the blast our sun would make if it exploded as a supernovae.
      Now for the good news: Our sun *won't* explode as a supernovae. It is too small to do that. Instead, it will heat, grow and swell beyond the orbit of Venus, shred its outer layers into space, and then collapse into a tiny whinny white dwarf star.
      Sleep tight!

  • @jordankloosterman2966
    @jordankloosterman2966 10 років тому +16

    I have to do my homework, but I want to keep learning

    • @davidshi451
      @davidshi451 10 років тому

      Is it possible to do…both? Probably.

  • @TheAAbck
    @TheAAbck 10 років тому

    only john can take something so complicated and explain so even the most average of people understand it thanks john u are the greatest educator of all time.

  • @rekahsoft
    @rekahsoft 10 років тому +2

    This is a spectacular episode. Thanks for all your great work!

  • @Jeanjellybean13
    @Jeanjellybean13 9 років тому +188

    maybe my husband and I will forego the ring and get an xbox as a symbol of our marriage :)

  • @csolisr
    @csolisr 10 років тому +27

    If the universe is built upon thermal disequilibrium, then it follows that the laws of physics must rearrange it back into equilibrium through entropy, right?

    • @Rodman200818
      @Rodman200818 10 років тому +25

      You touch upon a very interesting topic. You are indeed correct, the state of the universe, given enough time, will be of total thermal equilibrium. The key is "given enough time" though, we are talking inconceivable timescales, perhaps beyond other potential ends to the universe itself. No worries bro!

    • @Zazz30
      @Zazz30 10 років тому +7

      Yep. It's called "Heat death" if you want to look into it.

    • @csolisr
      @csolisr 10 років тому

      Zazz30 Knew it already. I've been planning to write a book on the relationship between that and neuroscience to prove that morality has no rational basis, but it'll take me time to have a solid base for it.

    • @Zazz30
      @Zazz30 10 років тому +6

      Carlos Andrés Solís Oh, I think I must have misunderstood the question then.
      What connection are you making between heat death and morality? It's not immediately apparent to me.

    • @Rodman200818
      @Rodman200818 10 років тому +1

      Zazz30 the relationship between the second law of thermodynamics and neuroscience can (or he will try to) prove morality has no rational basis, is what I gather from this. That is definitely out of my scope of knowledge but I'm not sure its a strong hypothesis to begin with. Flimsy connection. I'm all ears tho.

  • @SpiritSonic
    @SpiritSonic 10 років тому +2

    It's great to see Emily on the show-- I hope she can do more in the future!

  • @titchglover2601
    @titchglover2601 9 років тому

    Well done! Great video i had to learn this by viewing many of videos individually and piece it all together. And here it is now all pieced together nicely.
    Thanks.

  • @therodentman
    @therodentman 10 років тому +14

    the coldest star we've found is about a hot as a fresh cup of coffee

    • @davidshi451
      @davidshi451 10 років тому +11

      That's sooooo cool! Literally and figuratively.

    • @SeraphimKnight
      @SeraphimKnight 10 років тому +7

      Pretty sure that's a brown dwarf and not a star. By definition, a star needs to be hot enough to fuse hydrogen.

    • @dulipub
      @dulipub 10 років тому

      Those are dead stars cause by definition stars would need to have fusion going on.

    • @Cornelixx
      @Cornelixx 10 років тому +2

      why is there an account for a dick

    • @rayhs1984
      @rayhs1984 10 років тому

      watch the Scishow space video about the smallest star.

  • @TheKonkaman
    @TheKonkaman 10 років тому +8

    woo emily is back, she is my favorite

  • @militzer
    @militzer 10 років тому +2

    A technical correction. At 9:42 when you said “But elements heavier than iron can`t be created in the stars. There`s simply isn`t enough energy to fuse those heavier nuclei together.”
    That is not the reason. Up to iron, the fusion reactions are exothermic, meaning that even though you need a large amount of energy to start the reaction, when they fuse, they liberate an even larger amount of energy, that energy builds an internal pressure that keeps in balance with the external gravitational force. That is also the reason these light elements are the ones that would be used in a fusion reactor.
    After iron, the reactions become endothermic, meaning that fusing them actually reduces the overall energy of the system, effectively cooling the star. On the other hand, fissioning elements heavier than iron is an exothermic reaction, so should a star happen to fuse some iron, fission would occur to balance the external gravitational forces. That is the reason heavy elements are used in fission reactor and nuclear bombs.
    Google images “energy per nucleon” and you see that iron is in a "sweet spot", it is the “most efficient” element to store energy.

  • @Thiefree
    @Thiefree 10 років тому

    This tag team teaching technique is terrific. Ignorance and indifference don't stand a chance.

  • @SJY11
    @SJY11 9 років тому +6

    me at 11:09:
    yeah just some old ring
    me at 11:42:
    ill look at a ring the same way ever again

  • @ZiePe
    @ZiePe 10 років тому +3

    Oooh Emily is featured. Great!

  • @kraftthisile9113
    @kraftthisile9113 10 років тому

    I love hearing you guys!
    Thanks for the video!

  • @mikejia1
    @mikejia1 10 років тому +1

    just noticed how much nicer Hank's office looks compared to John's. Dat wood decor is just so warm and homey

  • @user-cn3ip6ok8p
    @user-cn3ip6ok8p 7 років тому +25

    Stuff like this makes me sad for two reasons:
    1. My existence is pointless.
    2. There is a lot of cool stuff that'll happen and I will never be able to experience it.

    • @alexanderpezzutto3875
      @alexanderpezzutto3875 7 років тому +2

      Ojaswini V that is, assuming all of this happened without a reason. However, if all this happened purposefully, then you too have purpose. Creation with a Creator has meaning.

    • @nathanmckenzie904
      @nathanmckenzie904 7 років тому +3

      Ojaswini V Your life and existence is what you make it

    • @dulguunmurunbarsbold210
      @dulguunmurunbarsbold210 5 років тому +4

      If you give it purpose, it isn't pointless.

    • @ahmeduchiha
      @ahmeduchiha 5 років тому +1

      your existence is pointless if the existence of the universe is pointless
      but if you're existed from the universe and its stars then how the universe came from?
      and this is the job of "God"

    • @isaiahsmith3199
      @isaiahsmith3199 5 років тому

      I would say the exact opposite, being you are a wayyyyy more complicated and interested set of particles and molecules working together than any sun, solar system, and a majority of living things on this planet. The fact that you can even comprehend "purpose" seems pretty spectacular when you consider everything else out there.

  • @gregjang5402
    @gregjang5402 9 років тому +8

    anyone actually pause and look at the introduction? the 'post human' part is the funniest... ROB...

  • @melissaabbey641
    @melissaabbey641 10 років тому +1

    I'm speechless. This series is mind-blowing and is helping me see everything in a new way, with new connections. THANK YOU

  • @robinchesterfield42
    @robinchesterfield42 7 років тому +1

    1. I love that Carl Sagan is in the intro! :) 2. I want John-From-The-Past's shirt in this episode. That is an awesome shirt. 3. Knitting grandma star. :) 4. This is all so weird but SO COOL. We are the universe trying to understand itself. And that is AWESOME.

  • @efe_aydal
    @efe_aydal 10 років тому +4

    Yeah! That's what I'm talking about.

  • @BraighGaming
    @BraighGaming 10 років тому +4

    If bending space is possible, we should create a wormhole that is very (very, very, very, very) far away, then put a super-crazy-high-powered telescope through it and watch the Big Bang. We could even use this technique (if it is possible) to catch a glimpse of earth during whatever time period we want. This would give us a solid understanding of the universe, with less guesstimates.
    Just a thought.

    • @EvansRowan123
      @EvansRowan123 10 років тому +1

      Bending space is dome by gravity, so we'd have to physically move stuff to where the other end of the wormhole is going to be, which takes more time than the time for light to cover that distance, so it'd be better to just use a telescope now without a wormhole at all. Plus I'm pretty sure specifically making a wormhole is way harder than just bending space around.

    • @BraighGaming
      @BraighGaming 9 років тому +2

      Rowan Evans
      I know that creating a wormhole is a lot more complex than simply bending space, but I wanted to put it in the simplest of terms so that anyone reading could easily understand.

    • @EvansRowan123
      @EvansRowan123 9 років тому

      Nathaniel King The "edge" of the universe doesn't work that way, if we could set up wormholes outside our light cone, the sensible places to put them would be like, between 1 and 1,000 lightyears away. No screwing around with the edge of the universe necessary.

  • @DonSmiths
    @DonSmiths 10 років тому +1

    As this episode ended, I was overcome by a sense of pride by being a Subbable supporter of Crash Course. I'm a big fan of this Big History series. Fantastic job Crash Course team!

  • @VitaminSoup
    @VitaminSoup 10 років тому +1

    Absolutely amazing ... and the way everything was presented was perfectly

  • @ChuDust
    @ChuDust 9 років тому +27

    0:33 "And I don't mean stars like Kim Kardashian, who is actually not a star - she is a person!" HAHHAHA 😂

  • @tri-slosher
    @tri-slosher 10 років тому +27

    Hey, if Emily is talking in this series, shouldn't she also be in the intro?

    • @davidshi451
      @davidshi451 10 років тому +6

      That's actually a good point… I think it's because she's not in all of the episodes?

    • @tri-slosher
      @tri-slosher 10 років тому

      ***** If that happens, I wonder what she'll be doing in the intro...

    • @thebrainscoop
      @thebrainscoop 10 років тому +4

      Sunwoo Kim Sciencing, naturally.

    • @tri-slosher
      @tri-slosher 10 років тому +1

      ***** Of course. Silly me.

    • @MadScientist3000
      @MadScientist3000 9 років тому +1

      too busy making sandwiches im guessing

  • @Death-ingrasp
    @Death-ingrasp 10 років тому +1

    Yay Emily Graslie! Thanks for having her appear on the show! I hope to see her more often too, I already subscribe to the brain scoop.

  •  9 років тому

    i really like the way you express these ideas, hope it gets more people into seeing your videos and getting into some kind of intellectual debate about it. keep up the great work!

  • @jack_the_sparrow
    @jack_the_sparrow 9 років тому +4

    "... THAT'S NUTS, (well it's more like cheese), BUT THAT'S NUTS!"
    God I love their brand of humor haha

  • @oshorrwarri5569
    @oshorrwarri5569 10 років тому +5

    What if there's a grapefruit so large, that it's larger then the universe?
    *Twilight Zone Music*

  • @porgy29
    @porgy29 10 років тому

    While I love all of the Crash Course's you have done so far this series is by far my most favorite. Partly for the great subject matter and the bringing together of so many different themes, but also due to the fact that I get to see both of the brothers Green and Emily.

  • @dewarfV
    @dewarfV 10 років тому +1

    Love seeing two of my favourite channels working together

  • @dr.kraemer
    @dr.kraemer 10 років тому +3

    My five year old daughter frequently tells me that Emily Graslie is her favorite scientist. Very glad to see her as part of this show!

  • @VideoGamerDerek
    @VideoGamerDerek 9 років тому +4

    the universe is awesome :D

  • @rushyahr7767
    @rushyahr7767 9 років тому +2

    I love these videos you guys make. It's nice to watch these when I start feeling down, because it really gives me something better to think about. I try not to watch too many of them though, because then I start to ask too many questions. I've been wondering for the last month if my dog is capable of remembering her dreams, for example. Then I'm trying to figure out how that part of the brain might work, and boy is that a time consuming endeavor. I think I just ask questions till I find that page of the book that no one has written yet. Then I want to write that page, and soon after I realize I don't know nearly enough to write that page.

  • @01jbeals
    @01jbeals 7 років тому

    Love these videos. Especially the ones about how our bodies work... I use this to help patients understand a wide array of how things & behaviors can effect your entire system. I am glad you guys are here to Educate people, & spread useful knowledge & information, ESPECIALLY in this particular day & age 😱

  • @JNava
    @JNava 10 років тому +12

    I know it may sound stupid & unreasonable but I've always wondered if our universe was a small speck of dust, like in "Horton Hears a Who". I've always thought that book was about the scientific curiosity overpowering the absent minds of religion & it's followers, Calling out blasphemy or heresy on questioning what's out there. It's crazy how a child's book can reflect on what grown ups wondered throughout history about the universe. I know it's just a silly book, but that image has sizzled & burned in my mind for years. I just want to know, what are the possibilities of mankind & it's universe, being simply a small speck of dust?

    • @HoneyvsClementine
      @HoneyvsClementine 10 років тому +5

      Well, I guess now I know I am not the only one with that theory...

  • @TheFuzzynutz65
    @TheFuzzynutz65 10 років тому +24

    No offense but i now have to wonder how accurate your info is about the big bang considering mount rushmore is not in north dakota but it is in south dakota.

    • @lucasruano2283
      @lucasruano2283 10 років тому +3

      They a simple mistake and that makes you wonder about the rest of the show?

    • @ArticWS
      @ArticWS 10 років тому +196

      You missed the joke? Really?

    • @SethPanning
      @SethPanning 10 років тому +124

      it wasnt a mistake it was a joke

    • @sanitd1
      @sanitd1 10 років тому +45

      you guys didnt read the box?

    • @adamdifilippe8066
      @adamdifilippe8066 10 років тому +65

      That was a joke, dude.

  • @travistdwp
    @travistdwp 9 років тому

    This series is awesome. Keep it up, guys!

  • @kipofthemany2213
    @kipofthemany2213 9 років тому

    Dang I love this stuff. I haven't been on crash course in a while, so I didn't know there were new courses. Normally I stick to Scishow. But I'm so excited for this one. I like the big picture science stuff. Plus three of my favorite people on the internet are collaborating on this one. I am one happy nerd.

  • @xelgringoloco2
    @xelgringoloco2 10 років тому +13

    Who is Emily? Where's she from? She didn't introduce herself?

  • @Altorin
    @Altorin 10 років тому +21

    *looks at right hand* huh.. *looks at left hand* woah......

  • @IceMetalPunk
    @IceMetalPunk 10 років тому +1

    I love this series :) The way it connects the small and big, the simple and complex, the scientific and sociological together is something that I've always struggled to eloquently explain to other people. Well done and I can't wait for more! :D
    That said...I have a small nitpick. I understand the reasons why there are likely other "bubble universes" out in the cosmos that we can't see and may never see thanks to expansion of space...but why do we have any reason to think they'd have different laws of physics than our own universe?

  • @Avi-rocha
    @Avi-rocha 9 років тому

    Awesome! The best video I've seen from you guys! Great work!

  • @beigeleachon4461
    @beigeleachon4461 9 років тому +7

    What's so bad about BEIGE though?

  • @akhil151100
    @akhil151100 8 років тому +22

    2:07 I am offensive and I find that North Dakota

  • @alotbetter
    @alotbetter 9 років тому

    Thank you so much for this Video! You guys are awesome!!!!

  • @mczenk5095
    @mczenk5095 7 років тому

    I love this series, great work.

  • @zachcrawford5
    @zachcrawford5 10 років тому +3

    The annotation at 5:46 in claims that the Laniakea Supercluster is 500 light years across I think they meant to say 500,000,000 light years across (source: en.wikipedia.org/wiki/Laniakea_Supercluster and apod.nasa.gov/apod/ap140910.html)

  • @SomethingCleverAndOriginal
    @SomethingCleverAndOriginal 9 років тому +8

    WE ARE ALL STAR STUFF :D

  • @drevilatwork
    @drevilatwork 9 років тому

    Crashcourse getting better and better. Thank you very much

  • @UninspiredFilm5
    @UninspiredFilm5 10 років тому

    Emily!! I'm glad to see her getting involved in the Crash Course videos! :D

  • @burpilicious9687
    @burpilicious9687 8 років тому +5

    So I was technically born by a star's womb. AWESOME

  • @puffdaddy69
    @puffdaddy69 7 років тому +5

    Whose to say that the universe itself is a microscopic atom existing in a another world where "universes" are just atoms part of another piece of matter

    • @damonedrington3453
      @damonedrington3453 7 років тому +2

      BiG CRAWFS And that piece of matter is a fidget spinner that God owns

  • @awesomenessplus2757
    @awesomenessplus2757 5 років тому +1

    I love how Hank shakes when he yells about supernovas

  • @sockmaster2718
    @sockmaster2718 10 років тому

    Big History is my favorite Crash Course so far. This is awesome.