Let's Find Out - Drawing our Star: The Sun | ASMR [soft-spoken, space, science]

Episode Date: April 24, 2019

Our star, the Sun. As mysterious as it surely was to our ancient ancestors, it's no mystery why they worshiped and feared it. It's the source of all life on Earth. The sun warms our planet every day, provides the light by which we see and nourishes the plants that support the food chain we sit so precariously atop of. It can also cause cell death and make us blind. It could fit 1.3 million Earths inside its sphere. It produces poem-worthy sunsets and as much energy as 1 trillion megaton bombs every second. All of this, and our sun is just a plain old average star, by universal standards. It's really just proximity that makes it so special to Earth. We wouldn't be here if the sun weren't so close. So, how close is the sun? And how much space does it take to hold 1.3 million Earths? And while we're at it: • If the sun is in the vacuum of space, how does it burn? • What keeps all that gas from leaking into space? • Why does the sun send out solar flares? • Will it ever stop burning? LET'S FIND OUT… Thanks for watching.

nonsense that so often happens here on Earth. It's easy to forget that every clear night sky gives us access to a feature of the universe that connects us with the near infinite. Just look up for 10 seconds and really try to think about just how distant those stars, those heavenly points of light, really are. Some of you may recognize some of the other. Drawing. Peace out.

I'm just real quick. And maybe a little person excited about looking up at the night sky. So when you do, light you see travels around the entire earth. 7 per second. It takes even the stars you can see with your naked eye. And if you're lucky enough to be outside city limits, you may occasionally be able to glimpse a light that's traveled uninterrupted, still see them.

We can still see these balls of light, the material, all the matter that must be between how big must these colossal floating worms really be to spot them so far off? How powerful

are these churning furnaces so much light so far into the universe? What would it be like to fly up close? Forgetting that we're right next to one and the sun. As mysterious as it surely was to our ancestors, it's no mystery why they worshipped

and feared it. It's the source of all light and life. The sun warms our planet every day, provides the light by which we see, and nourishes the plants that support the food chain. We so precariously sit at. Can also cause some. sell death and make us blind. It could fit 1.3, produces poem-worthy sunsets, and has much energy as one trillion megaton bombs every second. All of this in our sun is just a plain old average star. Actually, one of the billions, I didn't remember that in our Milky Way, is one of, it's really

just proximity that makes it special to Earth. We wouldn't be here if the sun. So how close is the sun? And how much space does it take the hold 1.3 million Earth? What keeps all the gas from leaking in the space? Why does the sun send out solar flares? The sun is burned for more than massive, mostly hydrogen and helium. Because it's so massive, it has an immense gravity, enough gravitational force to hold all of that hydrogen.

and helium together and to hold all the other planets in their orbits around it we say the sun burns but it doesn't burn like wood burns instead it's a gigantic nuclear reactor is a star

the other stars we see differences distance the sun is only about eight light minutes away So the other stars we see are light years, tens hundreds, thousands of light years away. The sun is right in our backyard, many thousands of times closer. Equidistant from the other line, excessive approximations diagram that's going to be the extent.

I suppose the, I guess the sun doesn't really have definite boundaries. So we'll pretend that these fuzzy lines are on purpose. Go back over this with a pin to really get it nice and bold. This makes more sense now. I was trying to draw a cross section up the sun so we can break it down into all its layers. Officially the sun is classified as a G2 type star based on its temperature. and the wavelengths or the spectrum of the light that it. The sun falls between.

There are lots of G2s out there, and the Earth's sun is merely one of billions, made up of the same substance, only the same of helium and hydrogen. Some stars are extremely hot, while others are actually relatively cool. You can tell by the color of light that the stars give off. If you look at the coals in a charcoal grill, for example, you know that the red glowing coals

are way hotter. And just that same effect is actually true for a star. A blue or a white star is way hotter than a yellow star, which is hotter itself than a red star. So if you look at the strongest color or wavelength of light, I guess I... R star and so the wavelength called lambda is proportional to its temperature in degrees a star spectrum can also tell you the chemical elements that are in the star because different elements for example hydrogen helium carbon calcium absorb

light at different wavelengths and you actually have these if you isolate particular elements and I've done this in my any of you physics university students would have done it in your lab where you look through a spectroscopy microscope and you can see that when you actually found I found a great explanation of spectral lines and how the astronomers can identify the atomic composition of stars is so so damn interesting that different atoms all atoms have electrons

with their positive centers with protons and neutrons ethernucleus being the net positive charge of the atom and they're orbited by negative particles called electrons

electrons the star itself being disturbed by its own photons you know the ones generated from nuclear reactions at the core, or it's from other passing light from outside. It doesn't matter the electrons when they get bombarded with photons.

They actually jump. They have particular orbits, and I'll show you right here. We can see here that discrete orbits at a discrete distance from the atomic nucleus can jump, so as they can jump from one. one orbit and as you might imagine just as gravity kind of works here on earth which is interesting that that analogy kind of holds is that the further away they get from the nucleus the more energy would take to supply them to get them up there it's kind of like it takes energy to walk uphill

but you almost can lose gravitational potential energy as you go downhill so For the atom, for the electron to jump all the way to its outermost orbit, it has to absorb energy. And each atom, each different type of atom, like a helium atom, would be different than an oxygen atom in the amount of energy it would need to absorb to jump up. Interestingly enough, the word quanta comes from these very specific. gaps in energy that it absorbs. It, uh, for the electron to move, it can only absorb a specific amount of energy, no more, no less. So it's actual discrete levels of energy. It's not really a, you know, you couldn't just have two and a half joules of energy absorbed.

It would be exactly two or exactly multiples of two, two, two, four, six, eight, Of course those numbers are just made up for the example, but here you can see these are spectra. A fuzz on my finger. When an atom gets a helium atom reacts to only specific energy levels or specific wavelengths or colors of light. And each atom has a distinct spectral pattern. It actually absorbs. So if it's just bombarded by a bunch of light, white light being together,

Pacific wavelengths of light that it uses to have its atom, its electron jump up to a higher level, a higher energized. Analytizing the sun and other stars through a prism, astronomers can identify exactly what the sun or a particular star they're looking at is composed of in terms of the actual elements, the actual atoms, types of atoms that the sun has by viewing it through a prism in measuring the exact colors or wavelengths that are omitted on the other side of the prism, they can say, oh, I recognize this pattern, almost like a barcode, as heliums or hydrogens or oxygens, calcium.

And they say, oh, this star has an abundance of this element. And that's how they, that's one way that they're able to classify stars. So this is called an absorption pattern. Conversely, when an atom is charged already, just like anything, it tends to drop back down to its lowest energy state. And when it does that, it actually, instead of absorbing light to jump up, when it drops back down, it loses energy in the form by giving off a proton. Sorry, a photon.

A, that would be, I guess that would be nuclear fission. It would. So when the photon is released, and the electron drops back down a certain wavelength or energy level. And when it does that, it gives off the exact same spectrum, the exact same colors, wavelengths of energy that it absorbs. Is why stars can be classified, like the sun is classified as a G2, which I'll get into that, I'll probably do a very of that soon. And then stars have

their own spectra that we can identify them. Actually, I was just able to find a Hertzprung Russell diagram, I guess, it's called. And you can see here, G goes 0

to positive 15. So G2 would be just about here. And sure enough, that's in the yellow spectrum. It's right where our sun lies. So it's pretty interesting. You can see. It's a really cool diagram of all the different types of stars we've been able to classify just by observing. So the sun obviously isn't ice or water even. Sun is composed of gas. It can seem like liquid

in some circumstances, it's gas that in the core, I believe, has been stripped of all its electrons will find. You can think of the sun as structure, despite not being a solid object. The three major areas of the sun, so are radiative zone, or is the center of the sun comprising 25% of its radius. The radiative zone is the section of medium. immediately surrounding the core and it's 45% of its radius. It's the outermost ring of the sun. And then these two outer rings here are the photosphere, chromosphere, and then a hot mask that envelops the entire thing,

atmosphere and the boundary of the sun's solid body to the extent that it's very compact plasma or gas. Photosphere. The chromosphere is the area between the photosphere and the corona. So it's hotter. For some reason, it's even hotter than the photosphere. It's closer to the nucleus. To it than it. And also by the magnetic fields resulting from the movements of the gas by its immense gravity, which in a way might be considered the ultimate driving force of the suns. The fact that it compacts all the matter into the core to create the nuclear fusion.

In turn provides energy to rotate the sun along with gravity and churning up the matter manifest a electromotive force. But all this, of course, begins at the core. forgot to name Endromeda over here. 25% of the sun's temperature in the core is greater and 15 million degrees. Kelvin, a mass inward, and creates an intense, intense pressure. Pressure high enough to force atoms, atoms of hydrogen to come together in nuclear fusion reaction. something we have tried to emulate here on Earth unsuccessfully. So in the core, two atoms of hydrogen are combined to create helium-4.

So the first step is two protons, and I'll try to draw this over here. Hydrogen charge, but there's still going to be hydrogen atoms. And because the hydrogen atom, the element hydrogen, is defined as only having one proton we can define a proton as a hydrogen atom in a way H1, hydrogen with one subatomic particle in its nucleus words it doesn't have dancing in its core are going to be fused together. They're fused together.

There's a reaction right there shoots off. Reaction, two positively charged particles combine, they release a nutrient, you know, and a positron goes away, but even if you don't know what a positron is, you can cut it into it that one of these might have lost a positive element, a positive charge. And sure, sure as hell, that's what happens. That's what looks like what happens. And now we have a, and I guess a positron is essentially an electron, but with a positive instead of a negative.

charge. So now we have a hydrogen atom with two nucleic subatomic particles in it, one posit proton, one neutron. So it's still only one proton in the middle and remember that's the defining factor of an element. Helium has two protons, hydrogen has Deuterium, it's the hydrogen atom with one proton, one neutron. So the teutrium, in the core, surrounded by immense, immense pressure. So the deuterium is now going to combine with a lone proton again. Greek letter came two protons. It was actually, I guess, if you have two, the notation for atoms, having multiple of the same type of atom,

is down here in the subscript. And so this kind of pre-supercript is really what they use to define how many protons are in the nucleus. So let's just fix that real quick. Repeats. And you have two helium atom

in the same particle. Combine, no neutrinos, no gamma rays. So we have a bang. fusion right there and what's actually gonna happen ejected H1 a helium-4 atom so these reactions account for about 85% of the suns and an 18% comes from a helium 3 atom and a helium 4 atom combining to form a beryllium 7 atom which is 4 protons 3 neutrons in a gamma ray. The beryllium 7 atom then captures an electron to become a lithium 7 atom, 3 protons, 4 neutrons, or neutrons, and a neutrino. Then the lithium

7 atom combines with one proton because we can see there's a multitude of solo protons floating around to form two helium four atoms. The helium four atoms are less massive than the two hydrogen atoms that started the process. So the, and it seems counterintuitive, but that's because protons have a positive charge, and that charge ends up correlating with more mass. The energy emitted overall, so one, one helium-4 atom weighs less than two hydrogen atoms. The difference in energy now is because you have less mass.

The difference in mass, rather, is converted to energy as described by Einstein's E equals M, which is the mass of the particle times C, which represents the speed of light, squared. So, the energy is emitted in various forms of light, ultraviolet light, x-rays, visible light, infrared microwaves, and radio waves. Now the sun also emits energized particles, neutrinos, and protons that make up the solar wind, which is always barraging the earth.

This is what causes the auroras and occasional blackouts when it overloads. Our electricity, our electric grids. It strikes the earth, it warms the planet. It very importantly, it drives our weather. Our weather patterns here. Hurricane Irma right there. We aren't warm, in our magnetic field, of course, deflects a lot of this, the damaging radiation. to the poles, simply away, away from us.

So that's essentially what goes on in the core. It's combined until the atoms get increasingly more complex, more massive, the process, or radiate a ton of heat, light, energy, which are all characteristics of the same thing, the electromagnetic spectrum of length, proportional to the temperature or energy emitted. So after covering the core, it's time to extend outward. We're gonna see what happens with all this energy once it's,

once it finally makes its way out. Atoms are, old atoms are fused together to create new ones. Provides better contrast. Go back and retrace this one. And if you're wondering why I'm wearing a Band-Aid still, it's a, I guess, spin about a month ago now. I whacked my finger changing Molly's brakes and I got one of those black spots, you know, that form, whatever they're called. It doesn't, it's painless, it doesn't hurt, but it doesn't exactly look good for a thumbnail, you know.

The radiative zone is that extends outward from the core, accounting for about 45% of the sun's radius. In this zone, the energy from the core is carried outward. by photons or light units. As one photon is made, it travels about one micron or one millionth of a meter because it's so dense back there, or so dense at the core, before being absorbed, being reabsorbed by a gas molecule. And, you know, like we said, a core of the atom is surrounded by these, these, these, negative particles we call electrons which can only exist at certain definite orbits definite distances I guess from the center so these are negative and the nucleus is

generally actually it's always positive and as the reverse the order is is the electron emits the electron absorbs energy coming to it it gets bumped up to another. It gets bumped up by a quanta as it absorbs a specific, which is, I think, the smallest amount of energy that, who was in Niels Bohr?

I don't know, it was one of those early 19th, 20th century physicists discovered as it absorbs a specific unit subject to a bunch of energy it will naturally go down in its energy level, in which case, if it goes down, it actually releases the exact same amount of energy, which is the same color as the lines that it had absorbed previously. So upon absorption, the gas molecule is heated in the same wavelength.

So they re-emitted photon travels and slowly recycled, as you can imagine, this just happens. Micron by micron slowly work in its way into the convective zone. It eventually gets there though. So some might take even a shorter path, but they ultimately get there. So approximately in the gas molecule, of course, takes time.

and approximately 10 to the 25th emissions take place in this zone before a photon is able to reach the surface. So there's a significant time delay between a photon made at the core and by the time it goes all the way through and reaches the surface. God, that's so many.

And re-emissions take place. Infective zone, which is the final 30% of the radius. is dominated by convection currents that carry the sun. So these currents are carrying the sun's energy. Slowly but surely outward dorns the surface. These convection currents are rising movements of hot gas next to falling movements of cool gas. So it looks like a kind of glitter in a simmering pot of water.

actually yeah it's very analogous to that so if you're able to look at a clear glass kettle boiling I have a glass water kettle I guess

yeah it's called and you can actually see the translucent currents where the water looks a little bit almost like the kind of distortion of the image you see on a hot asphalt road. You see them rising, lowering, rising and lowering until the water boils,

in which case it's chaotic enough where there's no uniform upward heat in downward cool motions. The convection currents carry photons outward to the surface faster than the radiative transfer that occurs in the core in the radiative zone. So once the photons, does reach here, it's much more likely to more quickly get to the outer layer. The photons, the photosphere, chromosphere, and corona. There's so many interactions occurring between the photons and the gas molecules and the radiative and convection zones. Get this.

It takes a photon approximately 100 to 200,000 years. to get all the way out to the photosphere. But this photon, by the time it reaches our eyes, it's traveled, oh, it's, I don't know what the distance is. You know, it's traveled maybe 100, 200,000 miles, but it's taken 100,000 years, maybe 200,000 years, a quarter of a million years, just to get to the sun's surface.

And it shoots off, it takes only about 8 minutes, eight minutes to reach your eyes. So it's about a hundred thousand years and eight minutes old. We go out and bask in the sunlight. So travel out with the sun's atmosphere. The average distance from the earth is 93 million miles. So to here, and there we go. The radius, which is from the center, from the center to the outermost layer. layer before it reaches the atmosphere is almost half a million miles. So the radius, so let's see in the deadermost layer, is about 4,418,000 miles to the 30 kilograms. So 300 times the mass of the Earth.

God, that's so much. 99% of the entire solar system's mass. So even Jupiter and Saturn and then all of us terrestrial planets on the inner planets Only make up less than 1% of the entire mass of the solar system 25% helium heavier heavier elements that have been fused Kelvin again because it's not a solid object technically The center The center in the

poles. Just to see the light, darkness of space, I guess. Being inside the sun must be like just a heaven being like, except a lot hotter. It's an odd fusion of heaven and hell, I guess. But yeah, it must just be blinding. Obviously, there's no dark spots. Spots, they're just relatively, just like Earth, the sun boasts an atmosphere. So, however, the sun's atmosphere is composed of the photosphere. Photosphere is the lowest region of the sun's atmosphere that we can see. It's kind of like the surface of the sun. So this is about temperature. 5,800 degrees Kelvin.

It would appear much like the surface of a simmering pot of water. The bumps are the upper surfaces while the convection current cells beneath the objects that are creating these. The temperature drops and the gases, each cell, each little bump that represents the peak of a convection current, can be up to 600 miles across or a thousand kilometers wide through the photosphere. The temperature drops and the gases become, because they are cooler, do not admit as much light energy. This makes them less opaque to the human eye. And therefore the outer edge of the photosphere actually looks dark, in effect called limb darkening that accounts for the clear, crisp edge of the sun's surface. The photosphere to about 1,200 miles rises across the chromosphere from about 4,500 Kelvin, the way up to 10,000 degrees Kelvin. This is kind of counterintuitive, right?

The chromosphere is thought to be heated by convection within the underlying photosphere. As gases churn up in the photosphere, they produce shockwaves that heat the surrounding gas and send it piercing through the chromosphere in millions of tiny spikes of hot gas we call spikeules. So each spike-ule rises approximately 3,000 miles. above the photosphere and lasts only a few minutes. That's got to be at such an astonishing rate. Think about how fast they would have to go to go up 3,000 miles in just a few minutes.

Spikules may often follow the magnetic field lines of the sun, which are made by the movements of gas inside the sun churning up. So the corona, going to get to the... So I actually think that spikeule... are even smaller than solar flares. So we'll find out about those in a minute. This layer is layers underneath it. Extends millions of miles outward.

And remember the sun's 93 million miles. So it's a far distance, but still, that's a good percentage of the way all the way to Earth. Millions of miles. The corona can be seen best during the source. solar eclipse and in an x-ray image of the sun. The temperature of the corona averages 2 million degrees Kelvin, Kelvin. That's so insane. I'm not sure why the corona is so hot. It's thought to be caused by the sun's magnetism. So the corona, what I guess we notice as sunspots, the corona has bright and

dark areas. The dark areas are kind of thought to be the areas where, we're not as we're where the solar ejections escape. The lightly cooler areas relative to the thought-to-be tunnels through which the magnetic field breaks and charged radiative particles escape, traveling ridiculously fast. So, let's, from here, let's go ahead and take a look at the last little bit that we're going to be talking about

in regards to the sun. These are sunspots, solar prominences, and solar flares. So sunspots proper appear on the photosphere. These are, like we said, dark cool areas, and they actually often appear in pairs. So if we draw something like that, or skin of the sun, I guess. magnetic fields

about 5,000 times greater than the Earths and they break through the surface and these field lines leave through one spot twisted searing hot matter travels you know the corridor I guess is the best

a better word for it they travel along and sunspots actually occur in general the activity increases and ebbs and flows on an 11 year cycle called the solar cycle where these have a minimum and maximum nature to them of activity.

It's not known what causes them but the cycle, there's two hypotheses that are proposed to explain the cycle. Once an uneven rotation in the sun distorts and twists the magnetic field. lines in the interior and eventually they get wrapped around each other so much that they snap. And when this happens, they break through the sunspots. So as they do that, they snap and they have two loose ends and they break through random areas. And as they break through the gravitational field and the existing magnetic fields, pull them back in. pull them back in entry point I guess weak spots the second hypothesis for this 11 year solar cycle

is that huge tombs of gas circle the sun's interior at high latitudes and begin to move towards the equator when they roll against each other they form spots and when they reach the equator they break up and the sunspots decline to imagine that for a second just be like you have these huge It would be like having a giant worm on the surface of the sun. Perhaps these are pockets of lower density where it's easier for matter to travel through.

And it's interesting the dynamic between all these elements, so much heat and energy and, you know, just like hurricanes. In Florida especially, always form at the tail end of the hot summer in August, October, September, when the summer has already manifested in full effect and the heat has loud systems to create these funneling hurricanes and they always travel in very very similar paths so you can imagine maybe the sun has similar veins through which similar corridors of different air pressures, through which some activity, some matter, some more, particularly more fused, infused with energy or might pierce or might travel along,

occasionally of gases from the chromosphere will rise and orient themselves along magnetic field line. Sunspot pairs. These arches are called solar prominences. Dominances can last two to three months and can extend 30,000 miles or more above the sun's surface. Now, prominences can last two to three months of the surface. Inside, they can erupt for a few minutes or hours

and send large amounts of material racing through the corona outward. into space at 600 miles per second and they can burst and spew and they kind of snap and they spew it outward and these are called corona mass ejections imagine as scientists always do it's It's named perfectly based on its function, based on its, not function, based on its characteristics, its mass that's ejected through the corona. And it's going fast too. So I'm surprised they didn't call it a super fast coronal mass ejection. 600 miles a second.

These are the things that cause mass damage to our electrical grids here on Earth. if they're prominent enough to break through the Earth's magnetic field. So sometimes in complex sunspot groups, abrupt violent explosions from the sun occur, and these are called solar flares. And they're thought to be caused by sudden magnetic field changes in which the sun's magnetic field is concentrated. They're accompanied by a release of gas electrons. So we'll do, so gas electrons, visible light, ultraviolet light,

solar flares, visible light, x-rays. And this radiation and these particles reach the Earth's magnetic field, they interact with it and produce our auroras. They actually activate, they energize. Just like we said with the solar spectrum, spectral lines, they funnel around south, in the Arctic they do is excite, move up. They get momentarily charged.

They're absorbing the photons. But then, when the energetic impulse dissipates or already passes past Earth, there's no longer any energy bombarding the Earth, like before, and the energized electrons, like anything, tend to dissipate, into the lower energy state. And when they do that, they actually give off light and a specific wavelength, meaning again energy, wavelength, equating the energy.

And so those beautiful blues and greens that we see, I believe those are most abundant atoms in our atmosphere, which are nitrogen and oxygen and carbon dioxide, I guess. So if this is oxygen here it gets excited and what happens is actually it's called ionized an ionized atoms amounts of increases the negative charge on it and so therefore the ionization is just a word for an atom having a different charge changed by the the number of electrons that it has and so the auroras I'm spelling there wrong and so after the

energy is passed these excited electrons these excited atoms unized atoms they again revert back to their original energy state the least state with the least potential and so the atom goes

back down towards the nucleus giving off the beautiful light that we call auroras Yeah, and so oxygen atoms give off, I don't know the colors exactly, but different wavelengths than the nitrogen atoms give off. So you have blues and greens and sometimes yellows and reds, I think, when some of the more rare elements in the atmosphere get excited. So I think it's fascinating how intimately tied in to the sun's fate we all are and how much we rely on the sun and how much it gives us

you know for as ridiculously terrifying and powerful the sun is it's also the source of life on earth so it's the most important aspect solar system No doubt. And speaking of fate, the sun's fate is, of course, dependent on its age. It's 4.5 billion years old right now, so the sun is a balance between outward pressure, pull of gravity. Over its 4.5 billion year life, the sun's radius has gotten about 6% bigger. It has enough hydrogen to fuel and burn for about 10 billion years, meaning it has a bit over 5 billion years left. And during this time, it will continue to expand at roughly the same rate.

Expand outward runs out of hydrogen fuel. It will contract under the weight of gravity. however some hydrogen fusion will occur in the upper layers and as the core contracts it heats up and this heats up the upper layers causing them to expand and as the outer layer the radius of the sun will increase as it gets closer and closer to becoming a red giant star and so The airs start to expand due to the pressure from the remaining fusion of the hydrogen in the star. The radius of the red giant sun will be about a hundred times what it is now, lying just beyond. A red giant?

The sun at that point will completely vaporize. It will encompass, engulf, absorb, integrate the earth. and vaporize it. In some point after this, the core will become hot enough to cause the helium to fuse into carbon. When the helium fuel is exhausted, the core will expand

in eventually touching the cold recesses of space. It'll cool down, and the upper layers will expand and eject material. So once enough material is ejected, the solar ejected mass, the sun will dwarf. And eventually, it will further cool into a nearly invisible black dwarf. But the entire process, of course, will take billions. So I think we're safe for the next several billion years.

It's characteristics and, well, why it's so important to us. I hope you're able to learn something. And if not, I hope you're able to learn something. I hope you were able to get some good rest. Thanks for all your continued support. It means a lot. See you next time. Bye.