Creating the Elements - Sixty Symbols

[Gundogdogdog]

2:40 - That is pretty catastrophic.

[CertifiedBad4ss]

I thought our sun was in the size class that grows into a red giant when they die out?

[TracerTheGold]

catastrophic, catastrophic, catastrophic, (is that the only thing he says?)

[linkkid185]

The scientist in this video is cute :)

[damightyom]

The older you get you realize how little time you have to figure anything out...

[dalejail]

is it possible that there are more elements that we have not yet discovered out there in the universe?

[FreestyleCodShots]

@dalejail Yes.

[Wholoveschickens]

@dalejail while yes its possible it is far more likely that there are only undiscovered isotopes of elements we already know of. This is because elements with heavier nuclei than elements we know of tend to be extremely unstable and break down in a chain forming other radioactive elements until they are stable once again

I have no real qualification to prove what I say is accurate just a lot of internet searching and some logical deduction :)

[stuntyannick2]

@Wholoveschickens There could always be the island of stability tho

[vkotis]

2 people thought he was talking about an Oasis song

[briscocreek]

Very instructive, and clearly explained. I enjoyed this video immensely. The basic facts of science are mind boggling.

[laughomaniac]

Supernoverrrr!

[MultiPaulinator]

One thing I've always wondered is that along with the gravitational ricochet of the star's collapse, wouldn't the fact that a large percentage of the star's mass is undergoing heavy fusion also contribute a tremendous amount of force to the supernova, if not more force than the gravitational collapse?

[greeny202a]

Yes but the qur'an says fresh water and salt water do not mix!

[01rai01]

Look what happens when you give Hydrogen approx 13.7 billion years

[afa1234afa]

You got it wrong.

Everything start´ed with nothing!

Actualy nothing is  unthinkable power.

That´s my theory.

[AlexIsSmalll]

@afa1234afa ...what?

[afa1234afa]

@AlexIsSmalll He said let´s begin from the begining, an start from the big-bang, i´m talcking about the begining ..............................­...the "stuff" before the big-bang, let´s say 1M-year´s b.b.b (before big bang).

[AlexIsSmalll]

@afa1234afa with nothing at all happening (before big bang), there really is no time, since nothing is changing at all. right?

[afa1234afa]

@AlexIsSmalll how can we say nothing was happening b.b.b? it´s very difficult to explain time b.b.b because we are not talcking aboute month-year´s etc. we are talcking about time as a number, like what is the lowest number you know? im sure i can make it lower, or the higest im sure i can make it higer. My AFA theory is about the unimaginable exsteme force´s of nothing, it´s very difficult to explain, but easy to understand!!

[Semikindless]

@AlexIsSmalll You are right. The Big Bang itself created all the dimensions, one of which is time. It is just one of the dimensions, like length. The observing of it yet is spectacular for beings like ourselves. Time made evolving possible. Time was the one, that allowed molecules spread. Thank the basic 4 dimensions and the basic 4 forces for everything mate. These 2 4's are The Gods of physicists.

[Aviatorsmith]

@afa1234afa There is nothing before the big bang. Something may have led to the big bang, but that thing is in a different dimension from ours. The big bang created the current 6 dimensions we have in the standard model. That means before the big bang, time didn't exist. Without time, you can't imagine anything before the big bang.

[LamaPaj]

@Aviatorsmith Well, nowadays scientists are not so sure that nothing came before it. There are some really exciting theories of an ever expanding and contracting "oscillating" universe for an example.

[Wholoveschickens]

@Aviatorsmith no it is hypothesised that matter existed in a different state before the big bang and expanded at the time of the universes birth. Also pretty sure there are 11 dimensions currently believed to exist. It is impossible to measure anything from before the big bang and that is why time is considered to have started then

[Aviatorsmith]

@Wholoveschickens There are only 11 dimensions in the M-theory. There are other possible theories that do not involve that many dimensions such as loop quantum gravity and superstring theory.

[Wholoveschickens]

@Aviatorsmith o ya I've read that but I like the one with the big shiny numbers :P but no I just went by what I had heard I dont have a real clue and only a vague understanding at best

[Aviatorsmith]

@Wholoveschickens Oh yes. I like my space stringy too. Not foamy.

[Semikindless]

@afa1234afa Have you heard of a theory, that Universe lives cycles? See theory says, that in billions of billions of billions of years the Universe will implode (loads of details, cant actually fit them in 500 characters) and become singular once more. See, this process is very similar to how a heavy star reacts to imploding - it explodes, giving out extreme energy and heat. Now, think how much energy and heat would the whole Universe give out if imploded in a point as big as a Plank's length.

[afa1234afa]

@Semikindless Yes i have seen that theory, and it´s the theory that i like the best.

It´s just the start of the cycles, that disturb´ed me. So i made my own theory, to give my braine a rest.

[imlonecowboy]

@afa1234afa nothing can born from nothing... the universe is still a complex mistery to just say that everything started with nothing.

[gumme1234]

@imlonecowboy no, just no, the universe is simple, us humans are just morons.

[Skyclad65]

So everything starts with Helium? oh sorry Hydrogen He He

[jqs1943]

Sir, a sun is reminescent of a world in the making and it represents the core of a planet that will go through some metamorphic changes before reaching an stable status among other celestial entities. It's made up of gigantic spherical magnets which were made by the weave of some of the energies contained within the theta waves of the universe that are in escence all of the intelligence that there is.

[DjViOd]

I really want that first color image of a supernova (at 3:40) as my wallpaper

[TheRobster94]

Ogres are like stars. They have layers.

[UroborosComplex]

@TheRobster94 hahahahaha that's awesome.

[UroborosComplex]

@TheRobster94 hahahahaha that's awesome. but not like cakes though ..... even if they have layers too ...

[cosmiceon]

"super nover"

[FlashFizz]

I hope we see another supernova like the one in 1054 during my lifetime. It appeared at least three times brighter than what Venus ever gets.

[Acrimonator]

@FlashFizz Same here, I wait particulary for Betelgeuse...

[TheToxicRadio]

Supernover explosion

[kipras121]

So, theoretically there is chance that supernova explosion happened somewhere in the universe thousands of years ago and the light is till traveling towards Earth and it might reach it in the next 5, 10 or 50 years?

[thatsMrSmileytoyou]

@kipras121 We detect supernova almost on a daily basis so those odds of having one close enough to get a great look at sound pretty good to me, but the chance of it happening in the next 50 years is the same for that of 100, or 200 years, there's just no way of telling when. There are a couple stars out there now that we're monitoring daily for activity. Namely, the star Betelgeuse in the constellation Orion which is over 1000 solar masses

[kipras121]

@thatsMrSmileytoyou So would you be able to see the supernova of Betelgeuse through a naked eye?

[thatsMrSmileytoyou]

@kipras121 Well from the information I got; Betelgeuse is about 520 light years away. If that sounds far, our galaxy is about 100,000 across. Betelgeuse is also expected to explode as a type II supernova so I'd like to think that we could see it as a small fixed object in the sky from where we are, although it would probably take a really long time to look like anything that really stands out. Even the lowest powered telescopes will have a great view though

[kipras121]

@thatsMrSmileytoyou Thanks for your answers. I'm 15 now, so let's hope in my lifetime i will see it happen. =)

[puncheex]

@kipras121: Heh - it will, for a short time, 2-3 months, be brighter here than the moon. It will be plainly visible in the daytime sky.

[puncheex]

@thatsMrSmileytoyou: Betelgeuse has 15-20 solar masses. That's fairly large; the most massive known stars are in the 150-200 solar mass range. Betelgeuse has a radius about 1180 times that of the sun (if it replaced the sun, there'd be star nearly all the way to Jupiter), and so the volume is a billion suns.

[thatsMrSmileytoyou]

@puncheex Well then my information stands corrected

[robertwc82]

so, i am the remains of a supernova? thats pretty cool

[mangoismycat]

@gorgeous4376 not a song. retard.

[sbergman27]

It'd been wondering, lately, where the really heavy elements, like Uranium, came from. But I was thinking in terns of large stars getting to iron and then exploding, distributing what they had produced. But it sounds like the huge excess energy of the (super?)nova shoves energy into creating matter which would just as soon decay, later, and get back to a state of not having excess nuclear energy. So the energy given off by a chunk of radium on Earth is from a nameless (super?)nova somewhere.

[puncheex]

@sbergman27; Yup, that's pretty much right. Another source of some of the rare elements heavier than lead is the decay of even heavier isotopes. You're right about the excess energy available in a supernova, but it also creates elements like gold, who's common isotope is perfectly happy to be stable and not decay.

[sbergman27]

A good description never seems to be given the layman for this "bounce back" effect. The star runs out of what I think of as "exothermal" nuclear reactions, and starts running what I think of as "endothermal" ones. And that causes a star to release energy at a rate comparable to a whole galaxy exactly how?

[noxure]

@sbergman27 I think I can answer this. The collapse of the core causes an implosion, sending a shockwave through the outer layers. Those outer layers are still made off lighter elements and the pressure from that shockwave causes them to fuse at much higher rate than normal (pressure generated by gravity), which in term generates even more pressure; setting off a chain reaction. So the star basically explodes.

[sbergman27]

@noxure : Thanks. I see that now. And the outer layers are far enough from the center of mass that gravity can't contain the explosion like it could if it were at the core.

[thetotalvidwatcher]

What about the helium produced in nuclear fusion? How much of the helium in the universe today was produced in stars?

[puncheex]

@thetotalvidwatcher: Some of it, a small percentage as yet.  Notice that the percentage of hydrogen has not yet been significantly decreased, for two reasons: a lot of it has not yet been held within any star; the universe is not old enough yet, and secondly because only the hydrogen in the core of a star gets "burned"; the major bulk of the star is not sufficiently compressed to fuse, and so gets blown back out into space in the end unchanged by the whole lifetime of the star.

[nrgjunkie]

I did a symposium on GRB's and discovered Hypernovas. I want to know at what point does a Supernova become a Hypernova. Is there a solar limit on a Supernova? what is the maxium solar mass limit dictated by physics? I have heard numbers as high as 2000 solar masses.

[godofwar123786]

Please i love science, i wanna learn more, all these high words too lol..

like idk what means collusion..supernova, terrestial planets?? i wanna know. please help me out.

[AlanKey86]

@godofwar123786 The "terrestrial planets" are the solid planets, nearest to the Sun - i.e. Mercury, Venus, Earth and Mars.

[loserofnothing]

neutron stay collision!!! MUSEEE

[Ashitakaandsan]

Neutron star.... 10 km across...

[rithem412]

Technetium has been detected in red giants. Because technetium is radioactive, the technetium must have been formed during the stars lifetime, and not a previous supernova explosion. This proves elements heavier than iron are created during a stars lifetime.

[robertwc82]

so how many elements is produced by volcanoes on earth?

[clarkcolt45]

volcanoes doesn't produce them, they only spit them up from the earths crust and the core

[puncheex]

@robertwc82: None; there is not enough energy an any chemical reaction to fire a nuclear reaction. The only known natural occurrence of a nuclear reaction on earth was the Oklo natural reactor in Gabon, where conditions were just right to create a self-regulating reactor from concentrated uranium ores. It didn't get hot enough to melt anything.

[TheLockdawg]

whats the difference between a super nova and a black hole

[sidewaysfcs0718]

a supernova is the explosion of a star

a black hole is a star that collapses in on itself into 1 point called a singularity ...

[Medic1911]

@sidewaysfcs0718 if i stand correct, it is the bigger starts that collapse into black holes, correct? Why is it that they don't explode? I understand the force of gravity is higher due to the higher mass, but from the video I got the thought of Newtons law in my head. So why is it that the bigger stars dont have an opposite but equal force exerted thus a bigger explosion?

[sidewaysfcs0718]

@Medic1911

u dont understand

all stars explode at the end , after the explosion ..what is left is a white dwarf ...lots of new elements are sent away from the star after the explosion ..but the white dwarf is left very compressed ...to the point of collapse

if the white dwarf gets the chance to attract new matter ...it will get more mass until it collapses in on itself ..and becomes a black hole.

[Brookskyar]

@sidewaysfcs0718 after a supernova, nothing is left. white dwarf is formed when stars are compressed, but not by a supernova

[puncheex]

@sidewaysfcs0718: Stars that are less than about 4 solar masses more or less gently puff off their outer layers at the end of life and leave a white dwarf; it is compact but not compressed more than any other star. That is, at least some of the electrons still remain in shells around the nuclei. When a supernova ends the star, the result will be a neutron star (in which all electrons are freed from atomic shells), or, in extremely heavy stars, a black hole.

[puncheex]

... There are white dwarf stars which can attract matter off of a paired normal star. It will do so until the star reaches a critical mass, at which the entire white dwarf star becomes involved in a titanic fusion detonation; this is a class Ia (that's 1-A, the I is a Roman numeral) supernova, as opposed to the class II, described in this video. There is also the plain nova, caused by detonation of hydrogen on the surface of the dwarf, and Ib and Ic SNs caused by collapse of very heavy stars.

[puncheex]

@TheLockdawg: One of the causes of black holes is when an extremely heavy star goes supernova, instead of creating a neutron star at the center, the core is so dense that no physical structure can sustain it, and it collapses into a singularity.

[sciencerulez777]

God made the elements!

[xXbloodcoreXx]

damn you all beleave god exists you guys think god is a man with long hair and shit its not there is no god if there was there would be no problems in the world. no offence

[robertwc82]

and i made god

[begood20000]

@sciencerulez777 Then how comes he didn't write about them in detail in the bible ?

[Neutrinoghost]

I think i've spotted an error. At 2:00 the professor says "in more massive stars Helium is fused", after he's already talked about the Sun becoming a white dwarf. As a white dwarf is a Carbon-Oxygen core Helium has already been fused. You don't need a big star to fuse Helium, only Carbon-Oxygen+

[omaralmaini]

@Neutrinoghost

Yes, good point. That didn't come across as I intended. We do believe that intermediate mass stars like the Sun will undergo a period of helium fusion at the end of their lives, which forms the white dwarf core. Much of this occurs very rapidly in what we call a 'helium flash', lasting only a few seconds. More massive stars behave quite differently, switching on their helium fusion more steadily before building up the heavier elements up to iron in concentric shells.

[Neutrinoghost]

@omaralmaini Thanks for clearing that up. I've just finished reading 'The Physics of Stars A.C. Philips (S.E) 1999', I clearly didnt read it closely enough.

It does, however, state (P.61) "When helium fusion begins in the Sun, the core will consist of a classical gas of ions and a degenerate gas of electrons, with the electron gas providing the bulk of the pressure. The release of excess fusion energy into this mateial will be accompanied by an expansion and a decrease in the energy (cont)..

[Neutrinoghost]

..of the degenerate electrons but without any appreciable fall in temperature.  The rate of fusion will be uncontrolled. Thus, the onset of helium burning in the Sun will cause an explosive release of energy in a thermal runaway called the Helium flash" Then it states "Eventually Helium fusion will take place in a controlled way in a less dense core of non-degenerate matter"

So, roughly what time scales are we talking for He fusion after the He flash has occured? Thanks again.

[omaralmaini]

@Neutrinoghost

The Sun is likely to spend the final 1% of its life burning helium, i.e. around 100 million years. Eventually it will become unstable, pulsate and throw off the outer layers into space before finally becoming a white dwarf. For a nice description of the various stages try googling a lecture entitled 'The Once and Future Sun' by Richard Pogge.

[BlahKing101]

@Neutrinoghost: In stellar core temperatures exceeding a hundred million degrees K or so, multiple helium-4 nuclei can be fused to form carbon, oxygen, and so forth. Wiki "triple-alpha process" for more information regarding the subject.

[BlahKing101]

Sorry, misread Neutrinoghost's statement. I thought he was claiming that fusion of the heavier elements could occur regardless of core temperature and mass. Disregard my post. ^^

[Ducky1138]

"These are some of the things that hydrogen atoms do given fifteen billion years of cosmic evolution."

-Carl Sagan

[zdrastvutye]

i dont question your abilities, but the "bullet speed test" was the pure action in comparison to this. interesting would be the device that makes the alpha particles "visible" by condensation or ionisation.

[jesse0192]

I've been thinking about this for a few months now, how all the elements around us that make up everything we know are cooked up under enormous pressure inside stars, how all the matter is distributed when they explode... and I've also been subscribed to sixtysymbols for a while now... so how did I miss this video??

Lovely stuff, really makes sense of what I've been thinking about! Sagan's "star stuff" discussions always sit in the front of my mind when I'm looking around at nature.

[madman123456]

@jesse0192 A Supernova "Explosion" wont slow down in the vacuum of Space. So if a random Hydrogen Cloud that is cold and heavy enough to collapse in on itself to possible form a star and some Planets gets "hit" by some of the Stuff being hurled away from the Ex-Star, you may end up with a Solar System with heavy Elements to form terrestrial Planets.

Life on Earth is pretty much the result of quite a lot of very improbable coincidences.

[Ultimatley]

@jesse0192 yeah, in a few billion years we'll be back inside a star :)

[UroborosComplex]

@Ultimatley unless we can run away from the universe by using string theory :)

[Cusk0]

To heck with turning lead to gold, hydrogen is where its at. All you need is a supernova forge.

[Terr0c1ty]

i just got an erection.

[johnclavis]

It's spelled "electron".

[Neutrinoghost]

Glad to hear ir, theres a first time for everything.

[CarbonScience]

How come there is so much iron in the earth's crust if it's relativly rare in the space?

[furiousharry]

@CarbonScience i think its because the high melting point materials condensed closer to the sun, things like rocks and iron, cause as u go further away from the sun the composition of the planets change into lower melting point materials like methane and other gasses

[CarbonScience]

Yeah but our sun is made mostly out of hydrogen an it will stay that way for 4000000000 years or so. And they say that the earth was made out of the same stuff our sun was. So where did all the heavier elements come from? Meteorites? Supernovas?

Thanks for answers.

[Notyouraverageperson]

I do belive that just about every element heavier than iron came from supernovae. The rest was produced in nuclear fusion in the cores of stars.

[puncheex]

@CarbonScience: The earth tapped the same raw materials that the sun did originally, but the lighter ones "got away" because our gravity isn't as powerful as the sun's is; we're left with the dregs. The sun also has these same heavy elements, but they're diluted by the hydrogen and helium.

[Toml420]

That's right, there's a point in a forming solar system called the 'Ice line' beyond which the ices (methane, water, etc) can solidify and gather into bodies large enough to hold onto hydrogen atmospheres - the gas giants.

The solar system is indeed mostly hydrogen (compare the sizes of the gas giants to the rocky planets), but the Earth is too small to hold onto a hydrogen atmosphere, however, remember that there is an awful lot of water on Earth - H2O

[furiousharry]

@Toml420 :D im a proper scientist

[Digeridude]

It's left over from the early days when the sun cooked hydrogen into heavier elements. Clouds of heavy elemental 'discharge' surrounding the primitive star condensed into the inner rocky planets, while lighter gases formed the outer planets.

[mybibleread]

being a chemist with zero astrophysics background, I find the origin of elements speculative.

[Qtyled]

We know that elements may be fused together, since we can recreate these reactions on Earth using fusion reactors.

Observations of emissions from such reactors coincide with what we observe from the sun and other stars.

[Digeridude]

Being a gas station attendant with no knowledge of French cuisine, I find the origins of escargot speculative.

[DaDaWgLLS]

So your complete ignorance fuels your skepticism? That's not fair or honest.

[jozsefboviz]

What ewer this ,but god comeing

[2882890]

So thats how stars collapse!

Nobody could explain it as simple as that.

[silentelysium]

What an interesting video! Thank you so much for the really cool explanation of how elements are formed!

[andrewapotheosis]

This is an amazing video

[bevan306]

Love this channel

[xlrv1]

Supernova remnants remind me of a milkweed pod bursting in the meadow. Please don't fall into the awful "death star" metaphor. Those explosions are seeding life.

[skinnyjohnsen]

I wonder how the neutrons are actually made. A hydrogen and a helium atom creates a lithium atom is ok, but there should be just 2 neutrons there.

[skinnyjohnsen]

I wonder if you could make a video about it, please. There is little knowledge about it even among many of your subscribers.

[ginogrz]

When it comes to fusion inside of stars, the first step in the proton-proton chain cycle (one of many types of fusion that happens) is two hydrogen atoms fuse and in the process one of the hydrogen nuclei (a proton) releases a particle called a positron, which effectively turns that proton into a neutron. This is essentially how neutrons are formed to make stable isotopes of helium and other elements in star fusion (positron emission).

[seustaceRotterdam]

I see a nasty book on quantum mechanics on your desk! I am an organic chemist!

[pompeyjim12]

cool!

[imover18gotityube]

The crab nebula is my desktop wallpaper. :)

[Chipsonfire]

It's videos like these that make me slightly regretful that I became an engineer :-( Great video!

[NAMLegolas]

I thought Hubble's part was in yellow not green! :P haha Awesome Stuff! That's why I love astronomy

[BabylonLynx]

I just wanted to add that it's not rubber balls we're playing with here, to say that 2+1=3 and thus, a hydrogen and a helium would produce lithium.

There are parameters and physical properties that are different, the temperature and pressure needed to overcome the strong forces of the nuclei of both types differ, when the helium atoms are ready to fuses, theoretically, all hydrogen atoms should have already fused...

That is simply my point....

[BabylonLynx]

One question i have always wondered about...

We have about 90 elements naturally occurring, and through this theory I would say that the fusions would produce elements with doubled atomic numbers or at least even numbers like 1-2-6-12....

I personally don't believe that in order to get a lithium atom, a hydrogen and a helium atoms would fuse, simply because the physical conditions required differ between the 2 types.

Thank you for a wonderful but extremely brief clip!

[skinnyjohnsen]

Shurely you know that we fuse different kind of atoms together in labs today.

[BabylonLynx]

In "labs" we can do whatever we want to do, we can create supernatural conditions... But in nature is it possible to fuse a Hydrogen atom with a Helium atom... That was my question!

[bullfrogeth]

i'm sure it happens inside of stars all the time

[ginogrz]

Hydrogen and helium atoms do fuse in stars, but very rarely. When they do, they don't make lithium, but make helium-4 plus a positron and an electron neutrino. (don't worry about the neutrino if you don't know what it is). The emission of the positron means that one proton is changed to a neutron meaning it's helium instead of lithium.

Lithium is typically made by beryllium-7 capturing an electron and becoming lithium-7, or by helium-3 and 4 fusing and emitting a positron, becoming lithium-7.

[BabylonLynx]

Thank you for the explanation, but still these sets of "coincidences" can't have made all these 90 naturally occurring elements!!! it must be something else, call me crazy but what i believe is that the BIG BANG is actually a BANG of something massive that went in real tiny pieces and subatomic particles, and the matter is since then fusing together to remake this thing (apocalypse)

[BabylonLynx]

what i read about the pre-big bang period is that it had no dimensions, no mass, nothing! wut if it had EVERYTHING "one big cohesive universe" that exploded... i sound like a crazy person i know, with absolutely no scientific evidence, but logic!! the internal power of the explosion and the gravitational forces is set to recombine matter in this enormous state "the pre-big bang" which refer to as the big crush!

[GlyptiCa]

But where did 'everything' come from? You cant just have a big bang with nothing to start it. What was there to crush in 'the big crush'? These ideas suggest there was something before the big bang. Logic says there was. But we have to accept that we will never know.

[zombiesoiree]

"These ideas suggest there was something before the big bang. Logic says there was."

There was nothing before the Big Bang, because there was no "before." What we call "time" itself launches with the Big Bang.

[4jonah]

Okay, I've been wondering this for a while.

With the synthetic elements like 112 and 114 that were just confirmed, though they were made in a lab, the fusions were natural (albeit brief)

So I am wondering: is it POSSIBLE that elements like 112 and 114 exist in star formations, even for a split second?

If not, why not?

[BabylonLynx]

well, i believe they may exist in real massive stars, with extraordinary internal pressure than could induce the fusion of much heavier elements to produce the synthetic heavy elements, this is not observed through the wavelength-sensitive telescopes that gives a brief on a star ingredients, yet i personally don't believe that such extraordinary conditions could occur naturally

[xmaker1]

Don't Quote me but judging by the video I think what its trying to say is as long as the star can hold the gravity from snapping it is possible to form more and more heavy atoms past iron so although possible unlikely and that is why we don't see as much of the heavy atoms

[Yakzur]

You would be correct, it is possible.

[DuskY1991]

This is cool, awesome video.

[jagmarz]

So where do all the neutrons in the "metal" elements (Li - Fe and up) come from? Isn't the proportion of deuterium or tritium pretty low? Are neutrons formed in the cores of stars by some sort of electron/proton fusion process?

[Yakzur]

Neutrons were effectively cooked up in the big bang, and since they are unstable, had to bond with a proton to keep from undergoing beta decay.

I would imagine that your electron/proton fusion process hypothesis would be correct, since all you need to make a neutron is to fuse it with an electron.

[ginogrz]

There is an electron/proton fusion process, called electron capture, but that plays a small role in the formation of neutrons as far as stellar fusion goes. A lot of the neutrons come from something called positron emission, where a proton emits a particle called a positron and effectively loses its positive charge to become a neutron. This happens in one of the steps of Helium fusion, and also the fusion of heavier elements which require, as you mentioned, neutrons to be stable isotopes.

[farhmoha]

LOL my midterm is going have some of this material on it. Free interactive studying.

[TraceurZeno]

Very informative, thank you!

[kativilaga]

Thank you very much guys!

People that are learning or knowing a lot about space and stars... must see the world a completely different way.

Looking at things from these distances, this big, this old.. puts everything in a different perspective.

[leporidus]

»Cas A« = Cassiopeia A (4:31). Great video, but too brief as always.

[Slyyffer]

very interesting

[metabog]

Stars do everything alchemists would have liked to do. :)

[Ashitakaandsan]

@metabog helios.

[Badgerinthenight]

@metabog What a beautiful thing to say. :)

[TeamVacaville]

So... How did the Earth get all these heavy elements like Gold, etc. via Meteor/Comet/Asteroid?

I mean, I live on the earth, and we have most of the possible elements (some don't naturally occur, I hear), but the Earth wasn't once upon a time a supernova, was it? Where did Gold come from as far as the earth is concerned?

[cmxcmx]

If you look at it that way, you should also ask where the iron and carbon came from.

Stars die and sometimes explode and the results get scattered about space. All of that stuff including gold and other heavier elements "fall towards each other" because of gravity and that creates new stars and planets.

[7410n0]

Planets are formed from Nebula. The nebula that existed before the formation of the earth may have been a remnant of a supernova explosion or could have contained remnants of a supernova explosion.

[Superminyme]

When a star explodes it sends its remnants across the galaxy, as said in the video. That's a lot of remnants. These remnants can be gravitationally pulled in again, and become part of an accretion disk in another star, where things like planets are formed.

This is my best guess, for now.

[skinnyjohnsen]

Hey, kid, don't you know; We are star dust. We are golden. (Jonie Mitchell said that.)

[Lavabug]

Great video. Nice view of the books you've got there.

In case anyone's interested, an interesting read on this exact subject is Radiogenic Isotope Geology(Cambridge Press), it can be read freely on the internet.

[Acid113377]

simply amazing footage... thanks!

[havik1]

Good Video

Thnx guys!

[09876124]

AWesome vid :) thanks dudes

[v4lgrind]

Good start, but the end of the video feels a bit abrupt.

[Danthaman1971]

Yeah, i've got that feeling with almost all the Sixty Symbols vids...

The're too good for their lenght! ;)

[YogiToad]

thank you for this.

[TheJapanChannelDcom]

This must be one of the most intellectually provocative videos on yutube :-)

[welderb]

thanks!