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

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  • čas přidán 17. 05. 2024
  • 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
    -----
    You can pre-order my book ' Space: 10 Things You Should Know' as a hardback (UK only) or e-book (worldwide): bit.ly/SpaceDrBecky
    -----------
    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!
    ------
    Dr Becky Smethurst is an astrophysicist researching galaxies and supermassive black holes at Christ Church at the University of Oxford.
    drbecky.uk.com
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Komentáře • 1,2K

  • @ariochiv
    @ariochiv Před 4 lety +536

    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
      @clairpahlavi Před 4 lety +6

      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
      @danielparsons2859 Před 4 lety +2

      Yep. Dr. Becky rules!

    • @VincentGroenewold
      @VincentGroenewold Před 4 lety +12

      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
      @AlumniQuad Před 4 lety +2

      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
      @gammaraygem Před 4 lety +1

      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.
      czcams.com/video/ezHBuvDxihE/video.html
      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.

  • @Fabian-bg6cm
    @Fabian-bg6cm Před 4 lety +78

    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.

  • @sniffykmcbg2700
    @sniffykmcbg2700 Před 4 lety +56

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

  • @Ogmetaldad9155
    @Ogmetaldad9155 Před rokem +3

    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

  • @ZeroSpawn
    @ZeroSpawn Před 4 lety +182

    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
      @tncorgi92 Před 4 lety +14

      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
      @FireAngelOfLondon Před 4 lety +22

      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
      @PeaceMarauder Před 4 lety +3

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

    • @fromagefrizzbizz9377
      @fromagefrizzbizz9377 Před 4 lety +3

      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
      @mydarlinggirlrachae Před 4 lety

      @@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

  • @uprightape100
    @uprightape100 Před 4 lety +122

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

    • @DrBecky
      @DrBecky  Před 4 lety +16

      Yay Trig!

    • @dahemac
      @dahemac Před 4 lety +2

      So, trig for measuring a birdsmouth. 😉

    • @TheFeltbegone
      @TheFeltbegone Před 4 lety +3

      Dahhh, scribe to fit, beat to match. 😉

    • @Dr_Kenneth_Noisewater
      @Dr_Kenneth_Noisewater Před 4 lety +1

      3/4/5 FTW!

    • @billbaggins
      @billbaggins Před 4 lety +4

      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
    @MikeAben Před 4 lety +76

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

  • @marcusgrainger3329
    @marcusgrainger3329 Před 4 lety +24

    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!

  • @basisazombie
    @basisazombie Před 4 lety +77

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

  • @Neloish
    @Neloish Před 4 lety +44

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

  • @FireAngelOfLondon
    @FireAngelOfLondon Před 4 lety +5

    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
    @waynetokarz174 Před 4 lety +20

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

  • @LM53180
    @LM53180 Před 2 lety +4

    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!

  • @rogalewskip
    @rogalewskip Před 4 lety +3

    You're my favorite doctor, Doctor Becky!

  • @platypuschallenger
    @platypuschallenger Před 2 lety

    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

  • @neoanderson7
    @neoanderson7 Před 4 lety

    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.

  • @HotelPapa100
    @HotelPapa100 Před 4 lety +4

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

  • @tedbonbrake1967
    @tedbonbrake1967 Před 4 lety +4

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

  • @apk8340
    @apk8340 Před 2 lety

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

  • @thomasborgsmidt9801
    @thomasborgsmidt9801 Před 4 lety

    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.

  • @matthewsmusicshop
    @matthewsmusicshop Před 4 lety +3

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

  • @drshoes422
    @drshoes422 Před 4 lety +5

    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
    @raydenn6027 Před 4 lety +1

    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)

  • @pmwbison
    @pmwbison Před 4 lety +1

    Great job. I have only found your CZcams 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.

  • @enriqueboeneker
    @enriqueboeneker Před 4 lety +6

    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
      @IndianHeathen1982 Před 4 lety +3

      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
      @ahcapella Před rokem

      @@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?

  • @essaboselin5252
    @essaboselin5252 Před 4 lety +23

    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
      @Dragrath1 Před 4 lety +3

      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

  • @weschilton
    @weschilton Před 2 lety +1

    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.

  • @potterma63
    @potterma63 Před 4 lety

    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!

  • @PaulPaulPaulson
    @PaulPaulPaulson Před 4 lety +21

    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!

    •  Před 4 lety

      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
      @PaulPaulPaulson Před 4 lety

      @ 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 :)

    •  Před 4 lety

      @@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.

  • @matrixyoda
    @matrixyoda Před 4 lety +42

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

    • @MostlyChrisJ
      @MostlyChrisJ Před 4 lety +1

      Yoda Matrix is the monocle optional?

    • @williammakepeace36
      @williammakepeace36 Před 4 lety +3

      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
      @Ryukai-san Před 4 lety +7

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

    • @useodyseeorbitchute9450
      @useodyseeorbitchute9450 Před 4 lety +3

      Sorry, too White for woke left...

    • @TheStephenmonroe
      @TheStephenmonroe Před 3 lety +1

      But the Sun is visible during the daytime.

  • @Ireniicus
    @Ireniicus Před 4 lety

    Dr B is a fantastic communicator. Great job!

  • @Makz2000
    @Makz2000 Před 4 lety +1

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

  • @SigmarSich
    @SigmarSich Před 4 lety +10

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

    • @hopegold883
      @hopegold883 Před 4 lety +1

      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
      @YodaWhat Před 4 lety

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

    • @SigmarSich
      @SigmarSich Před 4 lety +3

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

    • @YodaWhat
      @YodaWhat Před 4 lety

      @@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
      @reinatr4848 Před 2 lety

      @@YodaWhat it's still os

  • @nlo114
    @nlo114 Před 4 lety +4

    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! ...

  • @awkweird_panda
    @awkweird_panda Před 4 lety

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

  • @lifesacardgame6454
    @lifesacardgame6454 Před 4 lety

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

  • @dons2281
    @dons2281 Před 4 lety +21

    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!

  • @francoislacombe9071
    @francoislacombe9071 Před 4 lety +9

    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. 😉

  • @edumathv
    @edumathv Před 4 lety

    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.

  • @ananyaworkashe8758
    @ananyaworkashe8758 Před 3 lety +2

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

  • @JakubH
    @JakubH Před 4 lety +18

    "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
      @DrBecky  Před 4 lety +11

      I did! I was so proud haha

    • @fredericloesch8578
      @fredericloesch8578 Před 4 lety +2

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

    • @adm0iii
      @adm0iii Před 4 lety +3

      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
      @gammaraygem Před 4 lety +1

      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.
      czcams.com/video/ezHBuvDxihE/video.html
      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
      @freddan6fly Před 4 lety +4

      @@gammaraygem You are clueless like a flattard.

  • @thegreatnovel322
    @thegreatnovel322 Před 4 lety +4

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

    • @denisdaly1708
      @denisdaly1708 Před 4 lety +1

      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
      @martinedwards2004 Před 4 lety +1

      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.

  • @raghu45
    @raghu45 Před 2 lety

    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.

  • @sadiquejk
    @sadiquejk Před 4 lety

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

  • @cavalrycome
    @cavalrycome Před 4 lety +4

    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
      @KohuGaly Před 4 lety +9

      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
      @dexter9313 Před 4 lety

      @@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
      @Hal2718 Před 4 lety +2

      @@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
      @DrBecky  Před 4 lety +6

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

  • @cpj93070
    @cpj93070 Před 4 lety +3

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

    • @LEDewey_MD
      @LEDewey_MD Před 4 lety +2

      Awesome video. Simply mind-blowing!

    • @humbleevidenceaccepter7712
      @humbleevidenceaccepter7712 Před 4 lety +1

      Trust me people, you need to see this!

    • @-johnny-deep-
      @-johnny-deep- Před 4 lety +1

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

    • @LEDewey_MD
      @LEDewey_MD Před 4 lety +2

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

  • @edibleapeman2
    @edibleapeman2 Před 4 lety

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

  • @TraneFrancks
    @TraneFrancks Před 4 lety

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

  • @larrybeckham6652
    @larrybeckham6652 Před 4 lety +5

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

    • @tdhanasekaran3536
      @tdhanasekaran3536 Před 3 lety

      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
      @larrybeckham6652 Před 3 lety

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

    • @Bouzsi
      @Bouzsi Před 3 lety

      @@larrybeckham6652 *shakes head* uhh what?

    • @larrybeckham6652
      @larrybeckham6652 Před 3 lety +1

      ​@@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
    @mikecrockett3669 Před 4 lety +3

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

  • @richtaylor6039
    @richtaylor6039 Před 4 lety

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

  • @FourthMatrix
    @FourthMatrix Před rokem

    They should play this video in high school science class. What an amazing presentation!

  • @inerlogic
    @inerlogic Před 4 lety +30

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

    • @condorboss3339
      @condorboss3339 Před 4 lety +4

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

    • @turkosicsaba
      @turkosicsaba Před 4 lety +5

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

    • @mikedrop4421
      @mikedrop4421 Před 4 lety +1

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

    • @nousernamejoshua1556
      @nousernamejoshua1556 Před 4 lety

      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
      @inerlogic Před 4 lety +1

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

  • @aarontyler9569
    @aarontyler9569 Před 4 lety +2

    This channel is my weekly astrophysics lecture

  • @Jirayu.Kaewprateep
    @Jirayu.Kaewprateep Před 3 lety

    This VDO is a lot more meaningful to me as it combined of those explanations, knowledge AND the Sun behaviour.

  • @ugoamaldi8056
    @ugoamaldi8056 Před 4 lety

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

  • @edwardus12
    @edwardus12 Před 4 lety

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

  • @rksnj6797
    @rksnj6797 Před 4 lety

    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.

  • @aner_bda
    @aner_bda Před 4 lety

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

  • @Zany4God
    @Zany4God Před 3 lety

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

  • @clareg845
    @clareg845 Před 4 lety +1

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

  • @TheRealFlenuan
    @TheRealFlenuan Před 4 lety

    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 ^^

  • @TheBoxBand
    @TheBoxBand Před 4 měsíci

    I learned much more than a semester in university just from this video!!

  • @worldgeektube
    @worldgeektube Před 4 lety

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

  • @4thArmoredVet
    @4thArmoredVet Před 4 lety

    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?

  • @michelthibeault5176
    @michelthibeault5176 Před rokem

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

  • @johncourt9580
    @johncourt9580 Před 3 lety

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

  • @cavok1984
    @cavok1984 Před 2 lety

    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

  • @mystic_tacos
    @mystic_tacos Před 3 lety

    Though I SUCK at math, and tbh I dropped out of high school, I typically understand these videos, this one broke me. I will have to watch it another time or two. I loved how she explained that it has taken many, many years and multiple geniuses to get to where we are.

  • @kevinberger2012
    @kevinberger2012 Před 4 lety +1

    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!

  • @aprameyanaganur2934
    @aprameyanaganur2934 Před 3 lety +2

    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
      @DrBecky  Před 3 lety +1

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

  • @cesarbojorquez7418
    @cesarbojorquez7418 Před 4 lety

    You make it so simple to understand and no assumptions

  • @s7edgekat610
    @s7edgekat610 Před rokem +1

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

  • @thegeop5906
    @thegeop5906 Před 2 lety

    I find it sooooo impressive that there are people who get to those solutions!

  • @GP-qb9hi
    @GP-qb9hi Před 3 lety +1

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

  • @PhysioDetective
    @PhysioDetective Před 4 lety

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

  • @geoffreywilliams9324
    @geoffreywilliams9324 Před 4 lety

    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.

  • @DavidSambrook1138
    @DavidSambrook1138 Před 4 lety +2

    I really enjoyed your book. Thank you :)

  • @Elephantine999
    @Elephantine999 Před 2 lety

    That was a great walkthrough!

  • @johnfuqua1143
    @johnfuqua1143 Před 4 lety

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

  • @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.

  • @jimcarpenter965
    @jimcarpenter965 Před 4 lety

    What an outstanding presentation. Thank you!

  • @obafgkm30108
    @obafgkm30108 Před 3 lety

    This is great! Thank you for making these videos!

  • @mystic_tacos
    @mystic_tacos Před 3 lety

    I SUCK at math but that fact has never stopped me from being fascinated by and loving all forms of science. This is an amazing video that I think should be shown to 7th and 8th graders in science class.

  • @johnkotches8320
    @johnkotches8320 Před 4 lety

    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.

  • @tomatosoup44
    @tomatosoup44 Před 4 lety

    Great video once again Dr. Becky!

  • @denewinch2498
    @denewinch2498 Před 4 lety

    beautifully explained - hopefully it will excite a lot of people about science - informed, informative and exciting

  • @Kombivar
    @Kombivar Před 4 lety

    Great episode, great jumper and seriously consider to make an album If these song samples are just so simply popping out!
    P.S.
    Great Book - I had a great time and I'm waiting for next one.

  • @sbkarajan
    @sbkarajan Před 2 lety

    To me, this calculation is more of fudging numbers with lots of unfounded assumptions, but that's how science works these days, so really good to know. Thanks Becky!!!

  • @volkerwendt3061
    @volkerwendt3061 Před 4 lety +2

    Thank you, simply brilliant

  • @AntoniGawlikowski
    @AntoniGawlikowski Před 3 lety +1

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

    • @DrBecky
      @DrBecky  Před 3 lety

      Wow! High praise - thanks!

  • @jeffevarts8757
    @jeffevarts8757 Před 4 lety

    Spectacular video, Dr Becky. Really.

  • @AhmadJZaigham
    @AhmadJZaigham Před 4 lety

    Thanks Dr. Becky I learned something new.

  • @ToddSproule
    @ToddSproule Před rokem

    A terrific explanation! Truly excellent!!

  • @SCIENindustries
    @SCIENindustries Před 4 lety

    really nice video, need more stuff like that 👍🏻

  • @benjaminomargregory2444

    Thanks Becky I’m new to your channel and you are so good at explaining things to newbies like me!🧐🤓🤪

  • @melmcintyre3211
    @melmcintyre3211 Před 4 lety

    Great video ,magnificent explanation , thank you

  • @toolzshed
    @toolzshed Před rokem

    Awesome video Dr Becky 🤘🏽🔥🌞💛

  • @ProfRonconi
    @ProfRonconi Před 4 lety +1

    Thank you for pointing out how much human effort went into assembling what we now regard as commonplace knowledge. I believe all science courses should begin with an overview like the one you've presented.

  • @adamc1966
    @adamc1966 Před 4 lety

    Great to see you in focus Becky :) Still waiting for your book in the USA.