How do we know how long the Sun has left to live? | 7 things we need to know

You'll often hear people say that the Sun has about 5 billion years left to live before it runs out of fuel. But where does that number come from? It's quite a simple back of the envelope calculation but there are 7 key things we need to know before we can do that...
For more on why E=mc2 see this article from Ethan Seigel: www.forbes.com/sites/startswi...
To find out more on helioseismology and how we "listen to the Sun" check out this lecture: • How We See Inside a St...
02:08 - the calculation of the lifetime of the Sun
05:23 - how we know the mass of the Sun
07:54 - how we know the distance between the Earth and the Sun
08:39 - how we measure the brightness of the Sun
09:44 - why E=mc2
11:04 - how we know the Sun is powered by nuclear fusion
13:35 - how we measured the mass difference between 4 Hydrogen atoms and 1 Helium atom
16:58 - how we know the core of the Sun is where nuclear fusion takes place (helioseismology)
19:02 - how we know how old the Solar System (and therefore the Sun) is
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You can pre-order my book ' Space: 10 Things You Should Know' as a hardback (UK only) or e-book (worldwide): bit.ly/SpaceDrBecky
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Follow me on Twitter: / drbecky_
And on Instagram: / drbecky_s
Don't forget to subscribe and click the little bell icon to be notified when I post a new video!
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Dr Becky Smethurst is an astrophysicist researching galaxies and supermassive black holes at Christ Church at the University of Oxford.
drbecky.uk.com

[@ariochiv]

This is a point that is often ignored by most "science popularizers" (and, unfortunately, many science teachers): that science is a process, not a list of facts to be memorized. Explaining how we know an answer is at least as important as answering a question. Kudos, Dr. Becky.

[@clairpahlavi]

Perhaps, if people knew there is no truth in science, nothing is ever settled, and no theory has ever been proven to be the "Truth", then perhaps the political purposes of the 4th Reich could be separated from humanity's desire to elevate itself above the status of biological robots serving any world order.

[@danielparsons2859]

Yep. Dr. Becky rules!

[@VincentGroenewold]

Not as important, knowing the meaning behind it is totally the point. I went through my homework when I was young, at a lower level, grabbing books of a higher level to be able to understand things. If not, I had a hard time memorizing things or simply "taking it for granted". It took me hours more, but am glad I did it. As Feynman once said "I learned early the difference between knowing the name of something and knowing something. "

[@AlumniQuad]

Yes, but simplistic answers allow the priesthood to maintain their monopoly as intermediaries between Science and the unwashed masses. _"If I omit the most basic questions about how humankind figured this out, then I'll look like a genius, and it'll generate an assload of obsequious flattery in the comments section!"_

[@gammaraygem]

Except, she forgot to mention (i guess not to confuse the unsuspecting public), that there are some major well known and unexplained problems with the suns nuclear fusion model...but, i am sure she can answer these questions. kzbin.info/www/bejne/m6urc6ised2cnqc Because, if the sun is not powered by nuclear fusion, her calculation is wrong. And we know there are stars like the sun that go micronova or give superflares at set intervals. How does she explain that? Why would our sun not do that at any time? There is geological evidence this happened before in earth history. Apart from the "end of the world" myths.

[@sniffykmcbg2700]

I always heard about the number, but never got how we got there. Thanks, Dr. B.

[@Fabian-bg6cm]

1/3rd of the way in and I can say with conviction, as a guy who watches hours of TY/day learning, this is one of the best explanation video's i've ever seen.

[@uprightape100]

Trigonometry is used in carpentry to calculate rafter lengths. Yay Trig!

[@DrBecky]

Yay Trig!

[@dahemac]

So, trig for measuring a birdsmouth. 😉

[@TheFeltbegone]

Dahhh, scribe to fit, beat to match. 😉

[@Dr_Kenneth_Noisewater]

3/4/5 FTW!

[@billbaggins]

I reckon geometry/trigonometry are the purest base for all math and science. All the answers are repeatable, predictable and non corruptible, a 2 dimensional triangle will always equal 180 degrees etc. Can't remember any of it now 🤦‍♂️ but I do remember learning to do it with a slide rule and a log book. Use it when I sometimes make a knife to determine the blade bevels. Thank universe for online calculators😁

[@MikeAben]

Absolutely great job with the "how we know" question. There needs to be much more of this in science education. Thanks.

[@ZeroSpawn]

This is what kids need to hear in Middle School to get them excited in math! Kids are always told to do math, but never shown it applied.

[@tncorgi92]

I spent most of my school years thinking algebra and geometry were useless, then graduated to the real world and found out differently. I agree that being given real-world examples of math would have piqued my interest more.

[@FireAngelOfLondon]

First day of trigonometry for me was just as it should be. Our teacher took us out into a field and we measured a long straight line from the base of a tree, then the angle to the top from the end of our line. We used this to calculate the approximate height of the tree using a tangent. Always that maths teacher would show us or explain to us ways to use everything he taught us. He even used the example mentioned in another comment about calculating the length of timbers needed to make rafters for a house. The way he taught it maths was never useless and never boring. Mr Booth, dead now but definitely not forgotten.

[@PeaceMarauder]

I used it for figuring out how to make a tire stick on a race track :P

[@fromagefrizzbizz9377]

It's really simple: math (just as anything else) can be taught well, or taught poorly. Traditionally, in good schools most of the sciences are taught by *doing*, and guided into understand how the result comes about. it's not straight pedagogy (teacher chanting rules from a book), but forcing the student to do and understand. Often straight math is difficult to teach that way beyond counting the result of adding 2 marbles to 3 marbles and getting 5 marbles. Common core in one sense is an attempt to make math more intuitively understood, but all too often it's either done badly, or the student's parents have heart failure because the teacher isn't sledgehammering the multiplication tables into their precious kid's brainz. It pisses me off, for example, that common core has such a bad name, that people invented it just to make kids stupid. No, it's the result of dozens of evolving methods, trials and seeing what actually DOES work BETTER whether the parents believe it or not. Sure some kids might do well in the older fashioned method, but in many cases they may result in not understanding math as well. Math appears to be most commonly taught starting with something easy to "do and understand" (playing with marbles), thru years of by-wrote, and not until you get to higher grades (or especially university) that the intuitive understandings of what was by wrote starts to appear. it helps to have a hobby that involves some stuff where STEM subjects help, and a good student starts to actually use the math. I was never a math wonk, but I knew several, and married one. I got taught it all, much of it pedagogically, but frankly I don't remember much of the detail and couldn't use it off the top of my head. But it's taken well enough for the sciences and technologies I work with to be intuitively understood, and if I really have to, I know where to refresh my memory of the detail. Much of education is NOT the detail, it's the method. To a degree, it doesn't matter what you're taught, only that you've developed a mental process to comprehend and learn. It's the intuitive understanding how things work, and the knowledge to know that there IS a math behind it, which you can cope with if you have to.

[@mydarlinggirlrachae]

@@fromagefrizzbizz9377 They want obedient automatons, not critical thinkers, otherwise every governmnet official would be doing life, or on death row. A practical method would be to have classes attatched to industry, not only would the child see the theory in practical application, but gain a working knowledge of the industry itself, and be multi skilled as a result. They don't want that. That want you to spend a fortune on learning one vocation, as the debt inhibits social mobility and you are stable exploitable labor. Housing loans are another method of fascillitating this. We are nothing but commodities to be exploited and cast aside when no longer of use.They do not care about us in the least

[@basisazombie]

It's a great day when a new Dr. Becky video is released! :D

[@johnsumner6593]

Sebastian Farkas love watching her

[@Neloish]

Really amazing format, explaining the bigger picture, and then filling in the gaps makes learning a breeze. Please continue this format.

[@marcusgrainger3329]

Love how answering such an innocent sounding question requires a century of scientific results from multiple fields. I never considered how we knew this, and your explanation was wonderful!

[@FireAngelOfLondon]

You are far better than most scientists who try to explain the basics of their fields to the untrained. Clear, comprehensible and all done with a touch of humour. Please keep this up as long as you are able, it is a valuable contribution to science as it helps to inspire the next generation of scientists, as well as entertaining those who are just interested but work in other fields.

[@waynetokarz174]

I so love how you break it down, then explain it so understandably. Fun learning!

[@Ogmetaldad9155]

Also on your mention of the utility of trigonometry, I was a sonar tech in the US Navy on a submarine and we used trigonometry CONSTANTLY to determine how far away something was that we could only hear. One path of sound directly from the source and one of the ocean floor. That gives us two triangles, one being the right angle triangle with our boats distance from the bottom being one leg and the "bounced" sound path from the floor being the hypotonuse, and the other being the one made up of the two sound paths. We derive the hypotonuse and the two other angles of the right triangle and that gives us one leg of the other triangle and the two "near"angles and we use those to derive the length of the direct sound path to the target sound source. If we need to know the surface distance between our map location (as opposed to our position including depth) another right triangle with our newly discovered direct distance as hypotonuse and our depth below the surface gives us that. Sorry for the book, but know that i COULD have written much more, but i love whenever i can bring this up. :p

[@LM53180]

Thanks for showing us the thought process of a physicist! They don't teach this type of critical thinking at high school, which is why so many students such as myself struggled through physics in college. Would love to see more videos like this!

[@drshoes422]

I love how you explain things, and you make it easy to understand even if we don't have degrees in science. You make learning fun.

[@raydenn6027]

I enjoy watching outtakes Becky at the end of each video. The information in the video was conveyed clearly and succinctly, all the necessary stuff without the fluff. I eagerly await the Dr Becky email every Thursday morning ( I live in Perth Western Australia)

[@PaulPaulPaulson]

16:03 He was the brother of the german federal president Richard von Weizsäcker. Btw, I love this kind of video with the back of the envelope calculation while breaking it down to the actual measurements needed. Hope to see more of it!

I am actually kind of impressed about how you got his name right... given the post is edited, probably not the first time..., but still!

[@PaulPaulPaulson]

@ I only edited it to add the second part. But I have to admit that I was on his wikipedia page before writing the comment. Didn't remember if he was his brother or half-brother. So I saw his name there. And his last name is in the video, too :)

@@PaulPaulPaulson there was a famous blunder in german television, when the brother became federal president... i don't remember the details, to long ago, but if 'tagesschau' doesn't get a german presidents name right, everyone who does should be held in high regard.

[@essaboselin5252]

Great video. A billion years here or there; that really gives you an idea of the scales involved when talking about the universe. I still remember how shocked I was when my physics professor worked out the derivation of Enstein's equation in class. It was so trivial - at least to a math major. It showed what insight there was to looking at the problem, and that something so profound was also so simple and elegant. (Too bad the same couldn't be said for quantum mechanics!) On a side note, I immediately thought of you while a friend was gushing on about the new Star Trek series focusing on Picard. One of the key plot points was a sudden supernova. Of all the questions that plot point rose, the one that stuck with me was, "Is there anyway a star can go supernova without someone noticing the process starting a long, long time ago? Maybe Dr. Becky is a fan and will discuss it some day." (Of course, the real answer is probably the writers know nothing about science, and not that there is some theoretical way for it to happen quickly.)

[@Dragrath1]

Yeah the efforts to try and understand high mass star formation, evolution and death is very difficult due to the short and extreme nature of such stars and the complex dynamic environments where they form. Astroseismology would in theory be a nice tool but in reality these stars are too dynamic with significant to extreme deviations from hydrostatic equilibrium that it isn't feasible. A more realistic mechanism would be if you could detect a sufficient amount of neutrinos from a star to determine what fusion reactions are going on in the core. The problem as you may know is that neutrinos are really hard to detect and plus that wouldn't tell you how far into each core reaction phase the star is. Of course as each phase gets smaller and smaller with Silicon fusion for example lasting only about a day that becomes less of a problem but it would probably be too late if things got to that point. Now for stars in our local universe the process of core collapse creates such an absurd amount of neutrinos that you should be able to detect a huge burst of them which within our local group at least could arrive before the star appears to visibly change outside. Thankfully core collapse supernovae candidate stars tend to be quite obvious before they occur and are relatively rare so it isn't a huge problem. Though we are astronomically speaking adjacent to a high mass star formation region which has played surprisingly significant effects on the course of life on Earth

[@enriqueboeneker]

Wow, Dr. Becky! Great video. It got me going, and was following it doing actually the math. (I’m sorry, for me to completely understand I need to do the math thing). So, when I was figuring out the life of the Sun, we had these figures: E = 0.003 released of the fusion of H to He Mcore = 2.0e29 kg Speed of light =3e8 m/s Luminosity of the Sun = 3.8e26 kg • m^2 / s^3 (I converted the Jules to standard units) So, that gives us the following equation: Tsun = (0.003 • 2e29 kg • [3e8 m/s]^2) / 3.8e26 kg•m^2/s^3 And this gives me a funky result, which is: 1.421e17 s ~ 4.5e9 years, and not 10.5e9 years... what did I do wrong? (Sorry about the inconvenience! Awesome video!)

[@IndianHeathen1982]

You are correct. You didn't do anything wrong. A slight mistake in the video I believe - the calculation gives how much time the Sun has left (rather than the total lifetime of the Sun). In addition, another assumption is made - the luminosity of the Sun won't vary greatly.

[@ahcapella]

@@IndianHeathen1982 Was Dr. Becky calculating how much time the Sun has left; or how much time the Sun has left before it runs out of hydrogen (to fuse) in the core, and evolves off the main sequence?

[@weschilton]

Great video, I love the perspective you give. Far too many people just don't understand the "how we got to this answer" part. They either just accept the answer or deny it... based on nothing more than their own personal beliefs.

[@pmwbison]

Great job. I have only found your KZbin channel a month ago and still working on all your older video. Enjoying every one. You make astronomy enjoyable and lets my think about space. Hard to find other people in the real world that wants to talk about these topics. Hope high school science teachers use your videos.

[@tedbonbrake1967]

LOVE this video!! I knew the math, but knowing how they came up with the numbers is enlightening. Yay, Dr Becky!

[@rogalewskip]

You're my favorite doctor, Doctor Becky!

[@richtaylor6039]

Excellent vid Bex! Tons of great stuff in this one. x

[@aprameyanaganur2934]

I see a trend in Dr. Becky videos. She explains how exactly we know the stuff we know, and that isn't seen in many people. Hats off

[@DrBecky]

Thanks 🤗 I think it’s so important to do that! Especially since it helps people to remember what we know as well 👍

[@matthewsmusicshop]

Thank you! I love knowing what, but it makes it so much better to also know the why!

[@matrixyoda]

You need to be on the BBC The Sky At Night as a presenter 👍🇬🇧

[@MostlyChrisJ]

Yoda Matrix is the monocle optional?

[@williammakepeace36]

When Maggie Aderin-Pocock first presented the TSaN she was so enthusiastic and knowledgeable,but she did sound like a schoolgirl on helium.

[@Ryukai-san]

Unfortunately it's produced by the BBC, she'd need to swap genders before that ever happened.... :/

[@useodyseeorbitchute9450]

Sorry, too White for woke left...

[@TheStephenmonroe]

But the Sun is visible during the daytime.

[@thomasborgsmidt9801]

1. That is Your best video to date - of those I have seen. 2. As a collegue of mine said years ago: Anything essential is just mental arithmatic. He was/is - in my view - correct. He (and I in all modesty) are economists; but the same principles apply in other sciences as well. Point being: If you get the ball park figure wrong, there is probably a basic principle, you are not taking into consideration - or you have oversimplified the problem. 3. Figures and estimates in astronomy and other siences is a weird zoo: Something is determined to an insane accuracy: The gravitational constant is determined to - I believe - 10 significant figures. With other factors you are jubilant to get a precision within +/- 50%. 4. Engineers and physicists normally look down their noses at economists - critisicing our accuracy. To this I normally reply: To the best of my knowledge: Physicists have only the vaguest ideas of what 80% of the universe actually is (black mass) - which is quite a big chunk of ingnorance. 5. Having said that: I contend, that economists repeatedly argue from misunderstanding of basic math - such as they differentiate functions that are not differentiable - heck, they are not even continious. If You look at the graphs for currency fluctuations and stock market it is abundantly clear, that the jerks do not have the remotest concept of logarithmic functions and growth (i.e. exponential functions) - and they claim to be experts: Which indeed is a claim, which in no way can lift the burden of proof - or even evoke a suspicion that they know what they are talking about.

[@edwardus12]

I love this new format, please give us more of it!

[@HotelPapa100]

It's very humbling to make oneself clear how much we really are standing on the shoulders of giants.

[@SigmarSich]

I absolutely love these explanations! P.S. Short tip: "~os" = most likely greek, "~us" = most likely roman.

[@hopegold883]

Oo! Thanks! At this point in my experience with the English language, And the two mythologies, I have a pretty good intuition. But that’s a really helpful rule!

[@YodaWhat]

That's good for Helios, but _counter-example:_ Mount Olympus is the highest mountain in Greece.

[@SigmarSich]

@@YodaWhat In greek its name is Όλυμπος , Olympos ;)

[@YodaWhat]

@@SigmarSich Yes, but that is _in Greek._ @Hope Gold, speaking English, could be misled by your general rule... at least when applying it to English.

[@reinatr4848]

@@YodaWhat it's still os

[@lifesacardgame6454]

Absolutely love this video. The step by step build up and reasoning is great. Thanks

[@sadiquejk]

Brilliant video - love this format ! - please do more "how we know" vids coz this is super awesome

[@nlo114]

What I'd like to know: If the nuclear fusion is taking place in the centre 10%, That means a hot ball of 140,000 km diameter. The helium mass already produced over the last 4-5 billion years is heavier than the hydrogen, so will gravitate to the core, meaning there is a ball of helium at the core, of less than 10% of the total sun diameter; say 5%. Does that now mean that the H>He conversion is taking place in a boundary layer between the outer all-hydrogen surface and the all-helium core? Next question; if the change takes place at a fixed pressure/temperature crossing point, can the actual reaction-layer thickness be defined? Just curious to see how this one pans out! ...

[@francoislacombe9071]

You know, they didn't have radar in the 18th and 19th century when they first accurately measured the distance to the Sun. Maybe you should have touched on the method they used, it also involved trigonometry. 😉

[@SaveWesternCivilisation]

18th and 19th century? Or 2300 BC?

[@edumathv]

Great video. Really good content. Great focus and audio. You nailed it. Your videos are amazing, how detailed you are on them. I'm sure you have lots of work to make them.

[@ugoamaldi8056]

This video is great and your channel is litterally fresh air on youtube. Thanks a lot.

[@thegreatnovel322]

What’s astonishing is the small fraction of energy we receive from the total output of the 🌞

[@denisdaly1708]

Well the Sun is a sphere, and a long way away. We in earth only occupy a tiny sliver/angle cone of its space. We are very happy that we get the small amount. Any more or less and .life would be difficult.

[@martinedwards2004]

It's cool to realize how little mass is converted into energy during fusion. That's what makes black holes so cool. When mass falls in and is then slowly radiated back out as Hawking radiation, it is a 100% conversion to energy. Since the HR output is inversely proportional to the size of the hole, the best energy source is a very small hole to which you feed matter at the same rate it's lost through HR. Result: a perfect mass to energy reactor.

[@JakubH]

"The whole core of the sun was a hot dense place, and then four point five billion years ago nuclear fusion started, wait!" That's incredible! :O :D looks like you thought it up right there at the spot, did you?

[@DrBecky]

I did! I was so proud haha

[@fredericloesch8578]

@@DrBecky Now we need the rest of the song :D

[@adm0iii]

Not for back-of-the-envelope. Hydrogen is like 73%, helium 25%, so like only 2% other stuff. The main inaccuracy in her method is that the Sun's fusion isn't constant, but changes as the Sun moves along the main sequence. That's why it's off by about 10%.

[@gammaraygem]

Someone else did, and she forgot to mention (i guess not to confuse the unsuspecting public), that there are some major well known and unexplained problems with the suns nuclear fusion model...but, i am sure she can answer these questions. kzbin.info/www/bejne/m6urc6ised2cnqc Because, if the sun is not powered by nuclear fusion, her calculation is wrong. And we know there are stars like the sun that go micronova or give superflares at set intervals. How does she explain that? Why would our sun not do that at any time? There is geological evidence this happened before in earth history. Apart from the "end of the world" myths.

[@freddan6fly]

@@gammaraygem You are clueless like a flattard.

[@apk8340]

The way you present and teach the matter is very refreasing for me. You have that gift in you.

[@GP-qb9hi]

This video is gold. That's how things should be explained!

[@cavalrycome]

7:59 What's a good way to determine when Venus, the Earth and the Sun form a right-angled triangle like that, though?

[@KohuGaly]

You can see the crescent of Venus when looking through a telescope. When it is "half moon", then you know the angle to the sun is 90°. In fact, you don't even have to wait for that special 90° position. You can always calculate the angle to the Sun by measuring the crescent. en.wikipedia.org/wiki/Phases_of_Venus

[@dexter9313]

@@KohuGaly I guess it's easier to precisely measure the 90° phase though (and to measure such an important distance as Earth-Sun distance, you want accuracy). A crescent is not as trivial of a shape as a straight line splitting a disk in half.

[@Hal2718]

@@KohuGaly Well that and we've been observing Venus for quite some time now and know when either of the greatest elongation points will be which is when it'll be a half Venus.

[@DrBecky]

It’s called the “greatest elongation” of Venus - it’s the point at which it’s furthest from the sun in the sky

[@dons2281]

My 2 y.o. daughter often insists that I sing this to her: Twinkle, twinkle little star Scientists discovered what you are Giant ball of hydrogen gas* Creating energy by converting mass When protons in a nucleus are ensnared E equals M C squared *it's not just hydrogen and it's mostly a plasma, but hey, it had to rhyme!

[@demonprincemeliodias6590]

I am speechless😑

[@HassanPlayz]

i had a very hard time believing this

[@HassanPlayz]

cus my three year old sis doesn't speak full words yet, let alone asking to me to sing

[@Makz2000]

Best explanation on every thing involved in deriving the age of the sun. Thank you.

[@awkweird_panda]

Really appreciate this format of explaining concepts. Thanks Dr. Becky💯

[@larrybeckham6652]

Always amazed that helium was discovered in the Sun before on Earth!

[@tdhanasekaran3536]

Helium being the most inert chemically and one of the lightest physically it was very hard to find it on earth for a very long time. Helium is the only gas molecule that can escape the gravity of earth and reach the space if left in open (if I am not wrong).

[@larrybeckham6652]

@@tdhanasekaran3536 Well, hydrogen, too - if doest active with something the way up.

[@Bouzsi]

@@larrybeckham6652 *shakes head* uhh what?

[@larrybeckham6652]

​@@Bouzsi "The first evidence of helium was observed on August 18, 1868, as a bright yellow line with a wavelength of 587.49 nanometers in the spectrum of the chromosphere of the Sun. The line was detected by French astronomer Jules Janssen during a total solar eclipse in Guntur, India" Wikipedia

[@mikecrockett3669]

This Yank thinks you rock! Thanks so much for these.

[@nosuchthing8]

Blimey!

[@TraneFrancks]

I found this to be one of *the* most fascinating videos you've done. Absolutely superb presentation.

[@Elephantine999]

That was a great walkthrough!

[@cpj93070]

Becky, have you watched the "Timelapse Of The Future" video by Melody Sheep on KZbin? it's a fascinating insight on the future of the universe.

[@LEDewey_MD]

Awesome video. Simply mind-blowing!

[@humbleevidenceaccepter7712]

Trust me people, you need to see this!

[@-johnny-deep-]

Chris - yes, that’s a very humbling video!

[@LEDewey_MD]

Highly recommend watching it on large screen with a decent sound system!

[@inerlogic]

"Between astrophysicists and friends" Great title for a podcast.... "I've gone American" Well... once you go American....... ;)

[@condorboss3339]

A billion years here, a billion years there, soon you're talking about a lot of time.

[@turkosicsaba]

... you become obese, get diabetes and go bankrupt because of healthcare costs?

[@mikedrop4421]

@@turkosicsaba yeah, but we have guns so we can then blow our brains out after all that happens.

[@nousernamejoshua1556]

Dr. Becky, I have a problem. A looping constant. Since you have sorta gone American could you please say "beer can" with your best Britsh form? And when you say beer can" does it sound like 'bacon' with a Jamaican accent? It's not very technical, buuuuuT, 😊 with your help I could cross this one off the looping bucket list. I liked the video. Therefore the cosmological constant can be interpreted as arising from a form of energy which has a negative pressure, equal in magnitude to its (positive) Energy density. Dismantaling the principles of identity. No idea what this means, it just sounded cool 😎 like your British, and your education, and talents - superb Suprano French, and Piano and Singing! And even I think I saw some ballet form once, certainly some dance. So. . . Did you say that our light spectrum is entirely helium based or neutrino based or hydrogen based? And or a mix with our predominate hydrogen atmosphere, oxygen, nitrogen. If it did burn most of the hydrogen as light process and then dark space and then reacting with our hydrogen to give light again. . . That would be like blinking, huh? 🙂😌🙂 And some Twinkling 😊 And are Fraunhauffer lines other elements from hotter, (more gravity) Stars? I don't like the whole electromagnetic plasma either, buuuuuT 😊if there is a charged particle it might bend in our atmosphere, (magnetic field) Like the ionic spectrometer? Which would make sun rays straight lines maybe. Positive attraction. If the sun is giving off helium and space is full of helium, giving us an atmospheric pressure, may be contributing to gravity and sound pressure, then maybe space is like a fluid dynamic and light is about constant pressure given off by the sun, that it has a constant tone. Iff there was less pressure would we have less light? I have no idea why some days the light is warm and some days it's not. Maybe it's the neutrinos moving through particles nudging them, (pressure variable) Giving temperature. I actually have no idea what I am talking about, it's probably some simple attraction that is neither electromagnetic or chemical. I don't think I will ever figure it out. I bet you will though. Cheers! Please Pray For China. 💙 👀 Thanks for the videos. 💜 👅 And fluffy sweaters. i'm over tired 😴 I like what you did with the office.

[@inerlogic]

@@nousernamejoshua1556 that's "dr Becky" not "ms"

[@platypuschallenger]

This video completely changed the way I looked at things and even the way I solved problems. I remember so much of it from just one viewing despite never memorizing anything and having watched it months ago

[@aner_bda]

I love this style of video Dr. Becky. I really enjoy the in-depth breakdown of physics.

[@TheRealFlenuan]

I absolutely loved this video and the concept behind it, explaining at length how we know what we know and the chains of logic stringing all the evidence together. I hope you keep doing videos like this ^^

[@edibleapeman2]

This was a STELLAR episode - information dense but exceptionally digestable. Thank you for putting it together for us.

[@ananyaworkashe8758]

wow, I was so amazed by Becky's best methods of teaching. Thanks Becky, Keep it up!

[@potterma63]

Hardly a day goes by I don't use trig. Not just for my engineering job, but for stuff around the house. People really have no idea what it takes to answer some of those simple sounding questions! Another great vid, Becky!

[@aaronmicalowe]

Loved this video, thankyou.

[@PhysioDetective]

I love your videos Dr Becky but this was my favourite so far.

[@Zany4God]

And we have another great teaching moment. Thank you, Dr. Becky.

[@Ireniicus]

Dr B is a fantastic communicator. Great job!

[@tomatosoup44]

Great video once again Dr. Becky!

[@clareg845]

Your such a brilliant teacher Dr Becky, I wish I had you as my science teacher in comprehensive

[@DavidSambrook1138]

I really enjoyed your book. Thank you :)

[@obafgkm30108]

This is great! Thank you for making these videos!

[@jeffevarts8757]

Spectacular video, Dr Becky. Really.

[@4thArmoredVet]

You're my new astrophysics guru. I can watch your presentations in their entirety and not be bored for a second. What is this power you hold over me?

[@naveenc812]

Loved the video ...Many Thanks

[@rksnj6797]

Well done! Brilliant way to explain the question and answer. I liked that you solved the problem and then went into detail about how the values used are determined.

[@mrjaffa1013]

Great vid! Love Dr B.

[@worldgeektube]

This is wonderful. A brilliant and engaging teacher with great material.

[@cavok1984]

What a fantastic explanation of such a relatively simple sounding question. It makes me appreciate the bigger picture and the process of how the suns age was calculated. Plus you make it understandable to a degree and present it very well. Dr. Becky, you have a long time subscriber. Keep up the great work

[@volkerwendt3061]

Thank you, simply brilliant

[@s7edgekat610]

Your most excellent excellent & elementary video on your whole channel. Very enjoyable watch

[@michelthibeault5176]

I love the way you explain it is so clear. Two thumbs ups Dr.

[@cesarbojorquez7418]

You make it so simple to understand and no assumptions

[@jimcarpenter965]

What an outstanding presentation. Thank you!

[@SCIENindustries]

really nice video, need more stuff like that 👍🏻

[@ToddSproule]

A terrific explanation! Truly excellent!!

[@kevinberger2012]

becky thanks for your great science videos. Thanks to your very understandable pronunciation, I can learn English in addition to the exciting astrophysics. its charming and authentic charisma makes it one of the best additions to reading a book or sitting in an auditorium and listening to science!

[@toolzshed]

Awesome video Dr Becky 🤘🏽🔥🌞💛

[@seabound1350]

This was great. Many thanks!

[@AntoniGawlikowski]

One of the greatest science videos I've seen on KZbin ever. Period.

[@DrBecky]

Wow! High praise - thanks!

[@neoanderson7]

I'm stunned people have the nerve to "dislike" a video such as this. Are they afraid of learning? Do they think the Earth is flat?? Thank you once again for enlightening my day. Many thanks to all the individuals who contributed to find out this specific question.

[@johncourt9580]

Hi Dr. Becky, what a brilliant video, great explanations with your incredible knowledge and great style and so beautiful to watch xx

[@expchrist]

Wow, you've really outdone yourself for this one!

[@AhmadJZaigham]

Thanks Dr. Becky I learned something new.

[@somethingseemsoff689]

Much love. Thank you !

[@raghu45]

I am 70 & I see a philosophical truth relevant to humans in this your one program! 👍🏼😊 You've shown an erudite explanation to derive the life of our sun. It is still an estimate, but it is the process that is the basis to build confidence into the estimate. This clearly shows the difference between science & religion, or reason & faith. Thanks again for the WAY you've presented.

[@kubilay1839]

Thank you Dr.Becky.

[@melmcintyre3211]

Great video ,magnificent explanation , thank you

[@johnfuqua1143]

Thank you Dr. for your work and effort in informing this old man, Enjoy your Vlog a lot.

[@markmongan]

Super cool video! You're a legend!

[@geoffreywilliams9324]

Miss Becky, or should I say Dr Becky, you are truly amazing.Your video on the life of the sun is just amazing ! ! ! Well done.

[@johnkotches8320]

Looks like you’ll cross the 100k subscriber mark soon. That’s testimony to the topics and the presenter being quite informative! Thanks for making complex astronomy and astrophysics understandable for science enthusiasts.

[@LEDewey_MD]

Brilliant! We have just blasted at light speed through an entire year of Physics, to find out how much time left our Sun has, from Dr Becky! Awesome! And on the topic of Spectrometry, I highly recommend episode 7 of "Cosmos: A Spacetime Odyssey", entitled, "The Clean Room", which talks about how Uranium decays to Lead, as well as the heroic work of Clare Patterson to eliminate lead poisoning in the U.S.

[@jonlambert321]

Thank you for explaining

[@mattkkr]

Great video! Thanks a lot!

[@aarontyler9569]

This channel is my weekly astrophysics lecture

[@panostriantaphillou766]

Seismology and trigonometry: also from greek! Excellent show. I plan to show it today to my son to help the understanding of acquisition of knowledge for his IB TOK. Thanks again.

[@danielvaughan4155]

I love this! Its mind blowing! Thanks for the education 👍😃