My mother recounted that she was outside her family home in El Paso (around 100miles away from the site) loading luggage into the family car when the sky suddenly turned ‘as bright as the noon day sun’ for several seconds and then subsided. She was 18 at the time. It was only much later that she found out what caused the event.
I visited the Trinity Test Site and stood in the depression created by the explosion. I have touched the remains of the steel and concrete tower stubs. It's a humbling experience to stand where humanity's history changes forever in an instant. I spoke to an old gentleman there, who was a soldier and witnessed the blast. He had an interesting story that a family was driving on a highway, north of the area, towards Albuquerque. They had a blind daughter in the back seat who woke up at the instant of the explosion and asked her parents if the sun had come up because she just 'saw' a bright light.....only explanation was it probably xray/gamma burst that had stimulated her optic nerves.....
X-rays/gamma rays stimulating your optic nerve is a real thing. Astronauts have reported occasionally seeing bright flashes when their eyes are shut, indicating a cosmic ray has hit their optic nerve. This phenomenon has been reported by astronauts going back to the Mercury program.
84 years in Phoenix AZ here. I recall witnessing 2 or 3 Nevada tests (~340 miles). I believe they all occurred just before sunup (sky not dark). My recollection is that the "flash" was of very short duration, similar to a photographer's strobe light. Bright white sky, horizon to horizon, but for only the smallest possible amount of time.
On a more mundane level, the physicist Richard Feynman was present but hadn't been provided with welders goggles like everybody else. So he closed his eyes and put his hands firmly over his eyes. He said that when the bomb exploded, he could see the bones of his hands clearly as if he was looking at an x-ray, that's how bright it was.
I’ve read several times that because he knew glass is opaque to ultra-violet (knowing obviously that the blast would generate intense ultra-violet) he sat in a truck cab and observed through the windshield. Maybe he also shielded his eyes with his hand.
@@bogeycrow1968 In his book he implies he wasn't actually invited (but went anyway) and there weren't enough goggles for everybody! He was a practical joker and always bending the rules, including opening locked filing cabinets and safe boxes. His story might be exaggerated.
@@bogeycrow1968 Yes, that's what he says in his book. Glass doesn't block it to that degree, however, if the intensity outside is really high. I'm sure he did put his hands over his eyes, he knew roughly what was coming!
I don't know how the algorithm got me here but your science, your clean editing and the no-nonsense, informative presentation of your video got me to stay. Please keep doing this!
The first time I saw that video of Oppenehimer, which was many years ago, I assumed right away that he was identifying with the warrior, maybe because I have the cultural background. Actually, the warrior's dilemma (and by extension, the human dilemma) is what the whole Bhagavad Gita is about. Thanks for an interesting video. 👍
It’s a great line to understand if said with a sense of wry, semi-sarcasm (paraphrased) when thinking of one’s _duty_ to do something destructive…”Oh, great, now I’m a destroyer of worlds.”
I know nothing about atomic blasts but a little re. daylighting. Your estimate of 50% of solar radiation being in the visible range is very good. The measured value at the surface of the Earth is 42-43%. I expect the percentage to be lower for extraterrestrial solar radiation as the atmosphere absorbs more selectively in the UV and IR bands. The percentage of luminous energy in an atomic flash will however be lower than that of sunlight. The solar spectrum peaks right in the middle of the visible band thanks to the temperature of the sun's surface being ca. 5700K. I suppose an atomic flash peaks well outside the visible spectrum.
Much appreciated! Thanks for watching and subscribing, and welcome to the channel! I hope you also have a look at the other videos. Comments, questions, and requests are more than welcome.
10 Suns would still be a terribly impressive thing to witness, but the poetry (and Gita tie-in) of the "thousand" is undeniable. I'd just been made aware of the other interpretation of "Now I am become Death...", and appreciated your explanation. I can't help thinking that Bainbridge's words are less open to interpretation: "Now we are all sons of bitches", which apparently Oppenheimer quite liked!
If the fraction of the total energy output that goes into the brightness/flux is constant, you "only" need a 2Mt bomb to get 1000 suns. That has been easily surpassed by thermonuclear tests. 7.5 times in Castle Bravo, and 29 times by the Tsar Bomba.
The band "Rush" has a title called "Manhattan Project" on their power windows album. The song mentions a light brighter than the rising sun and an August day. A good balled.
thanks for sharing this, I had no idea; I looked it up and the lyrics even contains a reference to the Hiroshima bombing "The pilot of Enola Gay Flying out of the shock wave," which the topic of my first video ruclips.net/video/IEsIXui-YS8/видео.html
~10 suns! I love the power of estimation, especially with physics. Dr. Diaz (this may be pedantic) do you think ~50% was a good approximation for the amount of visible light? I was expecting almost an order of magnitude smaller. I don't have good intuition for at least two parts of the explosion, the distribution of frequencies of light produced and the amount of light converted to visible later on. I would've guessed the amount of initial visible light produced would be ~5-10% but I don't have a good intuition about this. I imagine a huge amount of gamma and x rays produced. This light would be absorbed and reemitted (through Compton scattering?) at lower frequency (repeatedly) causing the air to glow further. I don't know how much this would convert but I think we can assume the air to be a black body radiator (for which the frequency curve is centered near the visible light frequencies). This sounds like it could convert another 5-20% (total guess)? Sorry for the long response but I would love to hear what you think Dr. Diaz.
pedantic comments are more than welcome! I honestly didn't try to get an exact estimate but just an order of magnitude; for this, I used the standard of 35% of the energy in the form of thermal radiation and then, on top of that, I took at 50% for visible radiation, this gives ~18% of the energy in the form of visible light. Therefore, I might be off by a factor 2, but for an order-of-magnitude estimate this is just ~1 :) The main point is that 1,000 suns appears to be just a literary license.
It's incredible to think humans actually did this and the fusion bombs which followed. Quite literally the power of a star being released on the surface of the earth. It must have been incredible and terrifying to watch one of these things in real life. I would love to have seen the Castle Bravo and Tsar Bomba tests from a safe distance!
I suspect that "1000 suns" isn't that far off for an H-bomb, whose yields are typically measured in mega-tons rather than the (now so quaint) kilo-tons 😞 !!!
It was said that a blind girl, I think that her name was Georgia Greene, who was riding a a car at least 50 miles away from the explosion, sctually saw the flash of light, pointed in its direction, and asked "what was that?".
I don't think there's any mistranslation or misinterpreting he knows exactly the bomb he created has the potential to end humanity and the planet he means it exactly as said he has become the destroyer of worlds in that moment
I fully agree that Oppenheimer knew exactly what the power of the bomb was and how it would be used, there is no doubt about that, despite the image projected of his naivete in recent films. I have no intention of cleaning his image or role. I appreciate the comment and I respect the opinion, but in the full quote Oppenheimer ends with "I suppose we all thought that one way or another" so despite Oppenheimer's well-know arrogance, there is a lot of room for interpretation.
Excellent calculation estimate. One thing that basically every media depiction of atomic weapons do is show these detonations as huge blasts of napalm. Nolan did a really bad job in the "Oppenheimer" where he displayed it with yellow-orange color. These detonations are so hot and so bright that they are essentially plasma for well over a second, and they glow violet-blue-white. The greater the weapon yield, the worse it gets. There are old test videos where detonations look red, but that's a combination of photographic filters which were not neutrally dense, but more like welding goggles, and decay of photographic film. In reality, the sight of it was profoundly scary and, as Oppenheimer said, most stood silent, shocked by the energy they've helped release. Nothing like in the film where people clapped and cheered. Nolan really had a nice opportunity to do it properly, but he made many bad choices.
As a person watching footage of nuclear explosion since I can remember and after all the hype about Nolan's depiction of the Trinity test I was so disappointed with the final result, clearly Nolan fired up a truck full of gasoline and thought that we would all buy it. I liked the film and I loved the building up to t=0 but the explosion was pathetic. It was almost as terrible as the depiction in "Fat Man and Little Boy" with that leaf blower over Oppie's face.
@@jkzero Yes, and even considering it was a form of biography, and even without personal expectations of the film going into technical details (I assumed it was going to be about his life and turmoils), I was still so disappointed when the main event came. Nolan was creative with usage of liquid suspension of mica, but the sluggishness of it and the dull, fiery color was a cold shower. It did not bring up the terror of apes unleashing something they can not control.
I enjoyed the calculation part very much. Beautiful presentation! Thank you for finally getting the answer: 10 suns! Love it. But when it comes to Oppie and the Gita, there are many problems. Ryder mistranslated the Gita -- and caused Oppie in turn to misquote the classic? Maybe, but that shouldn't be, since Oppie claimed to have "learned Sanskrit from a professor at U.C. Berkeley." Anyway, the snippet translated from 11:32 is simply wrong. The line is "Time I am" [kalah asmi], not "Death am I." (Out of the half-dozen translations I've seen, only Ryder mistranslates 'Time' [kalah] as 'Death'. WTF? This in turn means he misunderstands the whole 'story' but that's too messy to unravel here.) Also, Hijiya's monograph is slanted, verging on a puff-piece: According to him, there was only [1] science and [2] politics to worry about. What happened to [3] ETHICS and [4] war crimes? This business of Oppie's about "I let the adults in the White House decide those things" has always irked me. Oppie arrogantly buried a petition (mentioned on page 138, btw, as seen in the video @10:52 in the unhighlighted section) in which everyone EXCEPT him definitely had a no-civilians opinion, and did not see "us scientists as little people in the White House who should remain quiet like children at the children's table and not interfere with the adults" (I paraphrase, obviously). Oppie was a war criminal, and I'm sick of seeing all this adulation of him. (Also, John von Neumann was WAY smarter than Oppie and without von Neumann there would have been no bomb.)
The solar flux in outer space is about 1.34 kW/m^2. But the atmosphere absorbs a substantial fraction of that. At noon, at the Equator, with no cloud cover, you have about 1 kW/m^2. So it's more like about 6 to 7 Suns. Still, during the whole event, the intensity varies greatly from one fraction of a second to the next. The first of the two flashes, which occur in very quick succession, may be much more intense than those figures, BUT it's VERY brief, and the human vision system averages over some interval, some fraction of a second, so that subjectively, it will not be as bright as the maximum instantaneous value. Oh, and the color spectra are different for the Sun and the Trinity blast. In other words, to fully answer this question, you need a deeper analysis.
thanks for the extra details, you are right: a precise result requires this an many other details to be consider. I was mostly interested in an estimate of the order of magnitude instead of an exact value. In fact, some measurements show the first peak to reach "~80 suns" for a few milliseconds.
Correct as far as the actual intensity at the surface of the Earth at sea level when the Sun is 90 degrees above the horizon without clouds, but the resultant number of Suns would be more like 14 (14kW/m^2 / 1kW/m^2).
I wouldn't use solar constant as a reference point because it uses how much energy Earth receives in a vacuum. On Earth, even on clear midday the atmosphere acts like an ocean and we sit at the bottom of it. So we receive close to a third, even in tropical regions of what we could in low earth orbit, which is about 350 watts per square meter. It greatly reduces the efficiency of solar panels on the surface compared to low earth orbit.
Thanks for this, you make a very good point. It didn't occur to me to weight the atmospheric reduction on the solar constant. Using your estimate, if the solar constant is reduced by a factor 4, then instead of ~10 sun you would get ~40 suns for the brightness of the Trinity test. Thanks again, very good detail.
Wow, its even more tragic when given more context of the literature. Ultimately just like Mordin in Mass Effect 3 he had to be the one to do it. Otherwise someone else might have gotten it wrong. Very very wrong
It is true that over 1 second the fireball released enough energy to be comparable to 10 suns, but the reaction is over in a few microseconds. That means the same energy would be released in that few microseconds. That momentary flux was millions that of the sun.
11:02 It's not that others were more qualified to make political or war decisions, nor that he didn't make those decisions. By making the bomb, he *was* deciding. Nor should people "honor" their elders by submitting to wrong decisions. If a decision is wrong, it doesn't matter that an elder made it. It's still wrong, and should be opposed.
The calculations here are not very waterproof. 1. The estimation, that the energy was released constantly within 2 seconds is too rough guess. In reality, 80-90% of the energy is released within the first microsecond. Therefore, the maximum brightness might also be 2000 times brighter than the average brightness of first 2 seconds. I don't think eye witnesses refer to the fireball when they are speaking about the brightness of nuclear explosion. They are talking about the flash. 2. You use the strength of visible light in your calculations. However, the solar constant includes all the ultraviolet and heat radiation also. Less than half is visible light. 3. Solar constant is only ~1000w when measured on the surface of the Earth. 1300W is only in space, where there is no atmosphere. 4. Brightness is a bit wonky term, because some might argue that the brightness of explosion doesn't lower, when the distance grows. It only gets smaller. Luminosity would be more precise term. However, in stellar objects, brightness is used as a term in this weird way, I grant you that.
How bright was it, blind fold your face, then cover your eyes with your hands You'll still see the bones and veins in your body like and x-ray an still hurt and blind your eyes depending where you are Feel like a sun at noon
I remember reading somewhere about a young lady, blind from birth (I think it may have been the case that she didn't even _have_ optic nerves, but I wouldn't swear to it) who was a passenger in a car some 40 or so miles from the blast, I believe (again, iirc - 40 miles _does_ seem a little close for comfort!) Anyway, she SAW the blast. It was the one thing she ever _did_ see in her whole life. As such I would contend that unless one belongs in the more rarefied strata of the physics community, arguing about whether, and how much, the "Light of a Thousand Suns" comments were exaggerated seem rather like a case of 'splitting hairs', even if it was a question of orders of magnitude! Particularly so if the observers cited were as well read as their boss, and they were referencing the holy books. Even if not, one suspects that rather than trying merely to be literally accurate, they were trying to get across a 'deeper' truth. (Given the total nature of the lady's blindness, I suppose the 'light' she saw might well have been 'all up and down' the E~M spectrum. Probably that's mostly a medical question. Again, though -- nit~picking!) As for Oppenheimer's famous quote in the 1965 NBC documentary, I admit I always assumed he was being a bit 'grandiose' - although if ever there was a case of grandiosity being justified, this was surely it! If Willardstein and Ihia (spelling?) are correct though, and they very likely are, given that his words were surely edited at least somewhat for the NBC special, never mind the thousands of times we've seen that clip since, it seems like - along with everyone else on the planet, more or less - I failed to ascribe to the man's words the nuance they deserved. Anyway, some interesting nuggets here for physicists and historians both, I should think. Certainly, as a layman I found it interesting and revealing - nice little documentary. Thank You, well done!
I also recall the story of the blind young lady, I don't know whether it is true or part of the folklore around the Trinity test. I think you are right that analyzing literal comments/quotes quickly becomes splitting hairs, I do not intend to do that but rather use them as an excuse to get to talk about physics and topics that I find interesting. Regarding Oppenheimer's quote, there is no evidence or report of Oppenheimer's saying it or thinking about it after Trinity despite having a journalist (W.L. Laurence) on site, except the NBC recording 20 years after the event. I am inclined to consider this a case of false memory.
@@jkzero I suppose, if you'll forgive me stating the obvious, we can never _really_ know what somebody is thinking in their mind, and though I haven't read any of the biographies on JRH, I think it's probably not giving him, though a scientist, too much credit necessarily to think he would be conversant with the Bhagavad-Gita. Also, while in any other circumstances, to employ those particular lines might come across as just a little portentous (not to mention _pretentious!_ ) on that particular occasion, they _do_ seem particularly apposite, whichever light one may wish to read them in... if anything, one might say the passage was almost a little _too_ apposite, _too_ perfect to just come to mind to him at that moment! Even had he previously given some thought to something that might be appropriate for the moment, given, as you say, the presence of W.L. Lawrence, one might have assumed that that was the perfect moment to record the thought for posterity... I think it may not be _100%_ correct to say that in 1965 he was misremembering his thoughts in the moment, but certainly at the time of the interview he'd had the benefit of 20 years to structure and hone his impressions... It may well be that the key part is where, after the bit about "... Becoming Death, the Destroyer of Worlds", he kind of tails off saying "I suppose _we all thought that, in one way or another..."_ So - by no means a lie, but it does illustrate the process by which a more or less unformed impression can, over time, become the quote that defines a man. And yes, having first practically wrote an essay bemoaning the splitting of hairs, I had to go and top it by deconstructing a quote upon which, no doubt, whole theses have been written... I do wish I could remember who it was amongst those present on that morning - it may even have been Oppenheimer himself - who admitted something like "What did I _really_ think? Actually, I think, like everyone, I just thought 'Well - It Works -- Thank God!' "
I have always thought the blind woman story was false. If you are blind you are blind. Even if she was suddenly gifted a split second of sight she wouldn't know how to describe it because she had never seen anything to begin with.
well if you remember reading something, someplace, at some point, who are we to question that and not take it for absolute fact. Thank you so little for sharing that tidbit we need a lot more speculation, 5th hand guesstimations, and pure make believe
My grandmother once told me many years ago how they were testing these in southern Nevada in the early 50s. She told me a story about when she lived in San Diego at that time, went outside around 5am to get the newspaper, when it was still dark. Suddenly the whole sky lit up for a few seconds, and the sky had a weird red glow for a few minutes after. She knew it was an A bomb test in Nevada. Said it scared her so bad she went back inside and didn’t come out for the rest of the day. The fact that it lit up the sky that far away is insane.
Thanks for sharing such a fascinating story. As a kid I had the recurrent dream of witnessing the Trinity test. It was always terrifying but somehow beautiful at the same time.
wow, that's such a story! Yeah, that was the cover-up story for the day after Trinity. I hope your family was not affected by the fallout; many communities were affected
I did the calculation many years ago, I would need to recall the details, but if my mind doesn't fail me, the answer is that for an observer on the Moon, the Trinity test would appear as bright as Venus in the dark sky. Is that sufficient to cast a shadow? I believe not.
@@jkzero hmm so we’d never be able to direct a flash from any source off planet above us. Only our satellites looking for double “rainbow” (flash) straight down can detect then huh.
I like this interpretation because I don't like when people hold oppy responsible for the existence of nuclear weapons. Like they wouldn't have been developed without him.
To get pedantic the luminosity of 10 suns is true at 10 miles / 16km. Closer in it would have been higher. If my math is correct then at a distance of 1 mile / 1.6km the "illumination of one thousand suns" would be true. Not quite sure if this would be a survivable distance from the detonation though either from thermal or blast effects.
I am big fan of pedantry, so happy to get this. You are totally right; however, I would assume that one (Oppenheimer or any other witness) observes such an event, the reference is the observation point and not how the event would look like somewhere else. Otherwise, almost any bright object could be "brighter than a thousand suns" by choosing the appropriate distance.
The trinity test was so "bright" Feynman watched it without protective eyewear by using the windshield of a pickup truck to block UVA and as close as anyone could get to the detonation. en.wikipedia.org/wiki/Trinity_(nuclear_test)#CITEREFFeynman1985
I have read several accounts for things that Feynman did at Los Alamos and Trinity. Feynman was a great physicist and a fantastic educator; however, when it comes to his shenanigans I take them with a grain of salt. I don't say they didn't happen, but if you read "Surely You're Joking, Mr. Feynman!" you can tell that he tried to generate this mystique around him.
Another way to put it is considering the inverse square law, which applies to radiant electromagnetic energy. This law states that the surface power density disminishes in an inversely proportional fashion relative to the distance from the radiant source. Thus, at twice the distance, we get one fourth (25%) of the power density, and so on. The so-called solar constant, with its 1.4 kilowatt per square meter value, applies to the vacuum in space surrounding Planet Earth, located at an approximate distance of 150 million kilometers. Therefore, in order to get a 14 kilowatt per square meter power density - such as emitted by the Trinity flash - the distance from the Sun should be 150 million kilometers multiplied by the reciprocal of the square root of 10; that is: 150 x 10^6 x 0.3162 = 47.43 million kilometers. Mercury, the closest planet to the Sun in the Solar System is located at 58 million kilometers from the Sun, whose surface temperature is around 427 degrees Celsius. In turns, this leads me to estimate that, at the 47 million kilometer mark, that temperature could very well be close to some 500 degrees, Notwithstanding, the flash from Trinity was an ultrashort pulse, a few microseconds long. However, a sustained emission of 14 kilowatt per square meter could very well manage to induce an ambient temperature rise to 500 degrees, virtually roasting everyone around, even at a location ten miles distant from ground zero. This fact became readily apparent to the people present at the Castle Bravo Thermonuclear 15 megaton test at Bikini Atoll on March 1st, 1954. Although stationed on the deck of an aircraft carrier, distant some 32 miles from the blast, the general complaint centered on the tremendous, unabated heat, almost as if being subjected to the influence of a blow torch (!!!) - - - - - - - - - Regarding the fraction of visible light contained in the radiated energy by the flash, I guess the Planck Distribution for an incandescent source could possibly prove to be a most valuable aid in providing an acceptable estimate.
If I understand the calculation correctly, it is highly dependent upon the distance: perceived brightness is inversely proportional to the square of the distance from the explosion, such that at 19 miles (3.16x as far), the perceived brightness would have been equivalent to the sun. Similarly, a 1 MT explosion would, according to the same set of calculations, be 50x as bright from the same distance, though I hope no one would set up observers so close to that sort of test; presumably observers could be 7x as far away and get a proportional effect.
When I was an undergraduate, the head of the physics department at NCSU L. Worth Seagondollar was a nuclear physicist. When he was a graduate student, he got to work at Los Alamos on the bomb project. I heard him lecture on his experiences several times. It was enthralling. One point he always made was how incredibly bright the explosion was and how videos and pictures really could not capture this effectively. A week or so before the Trinity test, there was a lecture on safety procedures. At one point, an ophthalmologist gave his presentation on eye protection. The speaker wryly observed that if the bomb was 10 times less powerful that they estimated, there wouldn't be anything to worry about because the light would be too dim to hurt them. If the bomb was 10 times more powerful than their estimates, they wouldn't have anything to worry about then, either -- because dead people don't need to see. But if the bomb was about as powerful as they thought it was going to be and you didn't have eye protection, you might go permanently blind. The grad students had planned to use standard welder's goggles to protect their eyes. "The more the ophthalmologist talked, the clearer those glasses looked," my professor recalled. They decided to use a piece of electric arc welder's glass mounted on a piece of cardboard. In the attached video, Seagondollar explains what happened during the test. It's quite a story! ruclips.net/video/AsYGSqSzWcA/видео.htmlsi=yLjiyO4VOXkfOnp2
Oppenheimer was an interesting & COMPLEX guy. Also, I vaguely remember Teller (?) talking about holding up "welder's glasses" to view the blast which reminded me of taking shop class & having to learn arc welding in Junior High & wearing a helmut so is the light from arc welding on par with a nuclear blast?
Re the cartoon at 0:55 If you make a scale model where a nucleus is the size of a basket ball and a neutron is a ⛳️ ball, the atoms are about one mile apart, and the pit extends to jupiters orbits. Moral of the story: nuclei are much smaller than atoms and Avogadros number is really, really, big.
I agree with your assessment of Oppenheimer's words and his role. This video was presented very nicely and straightforward science. Your guesstimates appear better than many folk's claims of a more precise analysis. Observation and experience matters, eh? Great job, Doc, of laying it out for us lay persons.
Just discovered your channel, and you don't have a clue of how much success this channel will achieve in the next months/years. Top quality content, straight to the point with the right technical informations. Keep up🎉 BTW, just a curiosity of mine: from which country are you from? Cheers from Brazil!
thanks for your words, I appreciate the positive feedback. I just find amazing that other people find these topics of interest too. I want to make videos that are technical but without going into hardcore math so everyone can enjoy them. I am originally from Chile, although it has been many years that I left my home country. Greetings from Germany.
Thanks, I am glad you liked the video. I am always curious to know what brings viewers to the channel, were you searching for something in particular or did the 'mighty algorithm' find you?
@@LukasHerrKompetenz Thanks for sharing and I am glad the search algorithm brought you here, I hope you find the other videos of interest too and welcome to the channel.
The military personnel were 16 km from ground zero, and the scientific observers were 10,000 yards is an odd choice of units. Basically 16 km and 9 km. Almost like it was taken directly from google 😂
The military personnel were at the base camp 10 miles (16 km) from ground zero, and the scientific observers were 10,000 yards; those are the units on the official declassified reports of the Trinity test. I do not "take things directly from google."
The brightness of the fireball would also be inversely proportional to the solid angle subtended by it from the distance of observation. If it was smaller than the disk of the sun, then it would be proportionately more intensely bright. Also, the Solar Constant of 1360 W/m2 is measures at the top of the atmosphere, and is observed less at the ground due to atmospheric attenuation and angle of incidence.
You are totally right there, the brightness depends on the distance to the observer; however, in this case my interest was how bright the Trinity test was for Oppenheimer and the other at the observation bunker. You make a very good point about the solar constant, it didn't occur to me to weight the atmospheric reduction on the solar constant. Using the estimate of an average close to 350, if the solar constant is reduced by a factor 4, then instead of ~10 sun you would get ~40 suns for the brightness of the Trinity test. Thanks again, very good detail.
I worked in the photonics arena for over a decade, as well as photography and photoscience. It was interesting to see the calculations of the flux of visual energy. I also write what I call philosophic poetry, and seeing the Hindu text behind Oppenheimer's famous quote, was very interesting to me.
I am glad you found the content of interest, make sure to check the other videos, I am currently running a video series on the early developments of quantum mechanics
As a filmmaker, I cannot stress enough how weird it is to hear that something is brighter than the sun, let alone 10 times. Most people don't appreciate how insanely bright the sun is. Nothing competes with the sun.
Thanks for stopping by and watching. As a filmmaker, you might find of interest that before the Trinity test scientists didn't know how bright it would get so they prepared dozens of cameras covering a wide rage of settings. In most cases, the film was overexposed and plain burned. After the Trinity test, rapatronic photography was developed to properly capture the early moments of nuclear explosions.
Comparing this numerical value to that of the sun, as shown here, does not take into account that the sun is 93M miles distant, while 10k yards isn't even 6 miles.
The military personnel were at the base camp 10 miles (16 km) from ground zero, and the scientific observers were 10,000 yards; those are the units on the official declassified reports of the Trinity test. You can even found the official maps using these mixed units.
The perception of brightness by observers must have been affected by how the explosion illuminated the mountains and surrounding landscapes, perhaps more than the bright explosion itself.
you are probably right, most of the eyewitnesses reported that they could not see much through the googles and protective gear provided and many simply looked at the mountains rather than the Trinity tower
Glad it was helpful! For years I found the quote confusing and then seen it misused everywhere led me to make this video. Thanks for watching, I am glad my early videos still get views. I ran this series on nuclear weapons last year, I am now running a video series on quantum physics, in case you want to check it out: ruclips.net/p/PL_UV-wQj1lvVxch-RPQIUOHX88eeNGzVH
You found something closer to the truth and showed it to us. Thank you for helping clear up this misinterpretation of such a popular quote. This subscription was such an easy decision - no asking needed.
Nice to see a scientific estimate of the amount of (visible) light energy emitted. It's going to feel a bit warm at that distance if you include the infrared radiation. I wonder if it would be safe to set up 20 mirrors, all reflecting the sun onto the same place, then run through the reflection (wearing eye safety glasses) to get a rough idea how it might feel. At 9km distance, it is a surprising amount of energy still.
@@caleroby9483 There is actually a test range that uses sunlight to simulate nuclear light exposure. It seems much more than 20 suns though. There are videos of it almost instantly igniting a tree on the test stand. That is a large scale testing rig. No need to bother with the mirrors if you want to try it, just concentrate sunlight with a magnifier until the power per square cm is the same, then put a hand under it briefly to test. Much safer with the much smaller possible damage area and a lot less risk to your vision. Could swear I've tried it as a child and didn't feel too much discomfort until the spot got really small. Light coloured clothing (or any) at that power level, and for the brief amount of time would be good enough protection - as observed in the test footage with the soldiers about 20 miles away from a 1Mt test.
Nice; make sure to check the rest of the playlist on nuclear weapons and have a look at the running video series on quantum mechanics, it comes loaded with stories that can help outsmart even many physicists who have been thought erroneous narratives and even incorrect stories.
Visible light is a small part of the spectrum. I’d suggest it didn’t even get to 10x brighter than the sun? Don’t forget those who viewed the nuke were 93 million miles closer to the flash than that sun.
J. Robert Oppenheimer, and to a slightly lesser degree his brother, got such a bad deal. I so would have loved to have just met either one of them, much less to have serious discussions or to have J. Robert Oppenheimer as an advisor/mentor while I studied physics. The world would have been a much better place if we had only listened to him and those like him.
The synchronicity is exceedingly intriguing! I have been working on the answer since 1969, the one Halley, Newton, and Whiston introduced to science, by asking the right question to a very learned man at the correct time. Nobody understood the quote, and still don't, yet....... I know what Oppenheimer was taking about! The best example is to compare the Blinding Bright White Light of the ablating 2013 Superbolide footage, from below, followed by Two counter-rotating smoking vortices to the Two Chinese New Year Dragons that chase a Bright White Pearl, accompanied with Fireworks. The Omnipotent of essentially every Worldwide Tradition is from The Pleiades, the radiant of The Taurid Meteor Stream, our most recent. It is shown symbolically in Lascaux Cave Art, Gobekli Tepe, Tauroctony, and our children still carry on the exact same tradition, at the exact same time, going around asking strangers if it will be a bad or good outcome when crossing The Halloween Fireballs - The Taurids! We are at an equally crucial moment and ALL of us need to fully understand this concept, as there is sympathetic magic of debauchery to propitiate The End of The World - The Younger Dryas Impacts Theory / Fact and the lesser Burckle Crater Mega Tsunami as a misguided notion of transcendence. The message is saturated everywhere; from the weathercock, the seven spikes of the diadem on The Statue of Liberty, to The Aldebaran Colored Heifer! I compiled and published a compendium that proves it without doubt and have concluded that we carry a genetic memory of the horrifying traumas of our cyclic world of destruction, impact winter, clearing of the atmosphere, then renewal of life by knee jerking into denial and change the subject or scoff without rebuttal. We Anthropomorphized inner solar system space debris and its accretion into our reality, or lack of. The Superbolide phenomena have greater yields than our best, do they reach the thousand Suns mark?
Somos nuestras decisiones y acciones. Jamás será un mártir ni alguien que hizo "lo necesario", un mal necesario. Claramente, solo fue un mal y una verdadera lástima con tan brillante mente prestarse para ello. Por supuesto hubiera sido otro pero creo que pudo disuadir a las mejores mentes de su época a no participar en esta clase de proyectos así como los persuadió de hacerlo. Esa clase de física no tiene nada de "bonita" ni elegante.
Gracias por el comentario. Se respeta la opinión, sin embargo sólo quería clarificar que en el video nunca intento justificar las acciones de Oppenheimer y otros, simplemente aclarar una frase mal interpretada.
The steel tower was not vaporised at the trinity test bits of it were examined afterwards at one point a rocket scientist investigating potential use of explosives to launch rockets examined parts of the tower to see how the steel held up against the blast, the tower’s steel was warped and mangled but had not “evaporated”
This is news to me, I have clearly followed the standard narrative of the vaporization of the steel tower. Do you have any reference for this? Could you please share it? I am really curious to know more about this. Thanks!
@@jkzeroLook up Project Orion, where US scientists, including Freeman Dyson, studied using small nuclear bombs (under 1kt) to propel spacecraft, including launching them from Earth. It would have been a Pulse Engine, driven by a series of nuclear explosions. I recall reading that during the Trinity test, a round metal plate was propelled (I believe it was upward) but suffered little damage, except for some ablating. This led to the idea of using a pusher plate that would absorb the energy from the nuclear explosions, but would not be destroyed. The Orion team, which worked on this project in the 1950s, postulated that they could have a spacecraft visit Saturn by 1967!
That might a clever interpretation; however, I doubt (just my personal opinion) that a person observes something bright and describes it as "how would this look at distance from the Sun," most likely it would compared to the Sun at that point.
You can give a rough estimate pretty fast. A 300 m fireball at 10 km is about 25× bigger than the Sun -> 25× brighter. OFC the surface temperature was less.
It appears that you are just comparing the angular size of the Sun to a fireball at a given time; however, I would argue that angular size is not enough and the energy flux is crucial. Take for instance the Moon: it has the same angular size as the Sun (~0.5°); however, you would not say that "the Moon is as bright as the Sun." Also, for a fireball of 300 meters in diameter located at 10 km I estimate the angular size of ~1.719°, which is a bit over 3 times the angular size of the Sun, so could you please elaborate where the "300 m fireball at 10 km is about 25× bigger than the Sun" comes from?
@@jkzero I used nukemap, which gives about 290 m radius for a surface shot, which translates to a 400 m diameter circle, the bunker was at 9100 m, which gives us a 1/22.75 ratio, the same ratio is 1/108 for the Sun. The square of these two ratios divided is ~ 22.5. So it looks like that the surface of the fireball was about 1/2 of Sun's surface brightness.
Take a 1980s bulb flashlight and compare it to a modern LED flashlight with a smaller lens size. The LED flashlight with the smaller lens size is just brighter. The angular size of the fireball doesn't matter. It's the amount of visible light that gets emitted and the distance to it that matters.
Happy to hear that! Enjoy the other posted videos too and more coming soon. Thanks for watching and welcome to the channel! Curious to know how you found it, were you looking for something in particular?
@@jkzeroI was actually just scrolling through my homepage before I ate dinner so I had something to watch when I was eating. I found the video on “The math behind saving the enola gay” really interesting and clicked on it, and was anything but disappointed. I watched the whole thing, then kept watching more videos even before I went to sleep lol. Right now, I came back to rewatch this one, because I watched this one right before bed and didn’t fully process it.
@@Asterism_Desmos thanks for sharing how you got here and for binge-watching the channel. I am glad you found the content of interest, I cannot guarantee to take all requests but I am collecting suggestions, if there is any particular topic you are curious just let me know in the comments. More videos coming soon so stay tuned.
@@jkzero So far, I think the real world examples of how math and physics can be applied could be cool. And nuclear physics is always an interesting topic. Really, you’ve done amazing at choosing topics so far, so keep up the good work!
True, I guess a more complete title for the video would be "How bright was the Trinity test when compared to how the Sun looks in the sky at noon" but that would be a bit too long.
Has anybody seen an explanation of by how much the plutonium core was compressed in the Trinity/Nagasaki explosions. Would the compression of the core during detonation be visible to the naked eye?
thanks for the question; honestly, I had never wondered this before and, I replied somewhere else, now I really want to know. I think I got it, I am half way through the calculation; I promise a dedicated video to this in the near future.
@@Salien1999 I do not know the answer and when searching I found this "compression by a factor 2.5 to 3" but it was unclear whether this quoted range is for radius or volume. As promised above, I am working it out and I will post a dedicated video because I find it a very interesting question.
@@jkzero I'm looking forward to your results. In another YT video -- I can't remember which one -- there was a hint that the implosion caused the core actually to liquify! Wonder if that is possible. I guess as long as it was a roughly spherical blob for a few microseconds (nanoseconds?) it would go off anyway. And at this point you run into semantic questions such as what is a solid vs a liquid (metallic crystalline structure?). And it doesn't take long for the whole thing to turn into a plasma anyway. There's another subject to cover: how long this all takes. It's quite amazingly rapid. Far faster than even 1 frame of video.
I've read "grapefruit to lemon". Also, I've yet see anything showing how the "pit" was cast from the "urchin" getting encased in plutonium & all the other layers of stuff...this seems like a pretty tall order to figure that part out.
@@jkzero an interesting video you might consider making: with a breakdown of the maths involved - similar to what's shown in this video - examine the rope trick effect. The fact that _visible light_ was intense enough to vaporize the guy wires of various towers which housed nuclear test devices, is pretty remarkable..
Simple piece of analysis cuts through to the answer. 10 Suns. Gee, I love Physics. The bonus was the second bit, clarifying Oppenheimer's quote. Thank you.
There's a slight mistake there. The line "now I am become death" is not grammatically correct in English if 'become' is a verb. You would say "now I HAVE become death..." or "now I am becoming death...". This confused me for years until I looked into it. The form that Vishnu takes is named "Become Death"; almost as if 'Become' is his first name and 'Death' is his last name. "Become Death" is a proper noun So the correct quote would be: "Now I am 'Become Death', the destroyer of worlds..."
great that you point this out, as a non-native English speaker, the 'am' always confused me. I had to look it up because I thought the sentence was "Now I become death..." but the 'am' is there in all the transcripts of the interview, and once I read it I could not spot hearing it. I should point out that there are also discussions about this free translation done by Oppenheimer. In fact, for what I have read from people who can read the original scripture, the correct literal translation is not "Death" but "Time" so Vishnu claims to "become Time, the destroyer of worlds;" however, in the end Time here is understood as a metaphor for death, which would make Oppenheimer's translation somehow valid.
@@jkzero Amzing videos by the way! My PhD is in maths and whenever I try to explain things to people I get a glass-face...but you bring the maths to life--well done you!
thanks for the positive feedback; I am thrilled by the positive response to the videos, it has been great to find so many physics enthusiasts willing to get some math in addition to the stories
Whoops. I spoke too soon. The first time I've actually watched a RUclips video that got to the point WAY before I did. Anyway... . . . FUN FACT! What's consistently left out of the situation from the Bhagavad Gita, made famous after being widely misquoted by Oppenheimer, sounds to me like less of an existential Hindu threat and more like a temper tantrum thrown by a thoroughly pissed off Vishnu at some minor Hindu prince, who refused to scrub the toilets. Here's the direct quote of Oppenheimer quoting Vishnu: "Now I am become death, the destroyer of worlds!" Am I the only one who notices the rotten grammar of a Hindu god being quoted here? Is it just me, or does Vishnu come off as a pissed off five year old, about to throw a tantrum? Well, that's Vishnu, folks, a Hindu deity with the power to BECOME DEATH and DESTROY WORLDS, apparently. Anyway, after several hours of failing to get the prince to do the dirty work in Hindu Heaven, Vishnu was completely fed up... so, taking on his multiarmed form, Vishnu threatens this prince with the famous quote that Oppenheimer took WAY out of context when he quoted it - you know, the part when Vishnu grew extra arms and threatened some unknown Hindu prince with death and destruction unless he got to work mopping the restrooms in heaven... Oh! And in case anyone missed it, Vishnu threatened to destroy not just one world, but MULTIPLE WORLDS ! Assuming that includes planet Earth because Earth is the only world that, to the best of my knowledge still exactly fails to be plural must assume - with NOT EQUAL TO OR PRAYER THAN worlds - death and destruction! Because where are the other worlds? Oh it's referring to planet Earth? That's our world, folks. And I'm pretty sure it's the only one, for now. I hope Vishnu got the memo. NOW TIME FOR A PRESSING QUESTION... Why Vishnu thought he could threaten some anonymous Hindu prince with a threat to destroy WORLDS, still plural and still only planet Earth, would give a shit about our own planet, located in a remote section of the Milky Way known colloquially as the Orion spur, remains beyond me. Regardless, we can get an idea of how effective this threat was at getting the prince to scrub the toilets by merely looking around... FALSE ALARM! After looking around, I'm pretty sure I can confidently say that we're all still here. That includes the entirety, including myself and you guys, of planet Earth. Can someone confirm this, please? I need to get published in 'Nature' before I croak.
I am DEFINITELY NOT a Mathematician in ANY way, but tiyr CKEAR explanations are absolutely wonderful. Thank yiy gir producing and Presenting your Videos!
I know a lot about nuclear weapons from my time in the military and this was probably one of the best descriptions of the gadget shot that I have ever heard phenomenal summary of the process, I don't know about anyone else but I feel building excitement when I hear process of a fission bomb destinating. If you think that was bright, fusion bombs produce enough light to temporarily blind someone who has their eyes closed and their hands in front of their eyes, and is facing away from the blast!
My mother recounted that she was outside her family home in El Paso (around 100miles away from the site) loading luggage into the family car when the sky suddenly turned ‘as bright as the noon day sun’ for several seconds and then subsided. She was 18 at the time. It was only much later that she found out what caused the event.
I visited the Trinity Test Site and stood in the depression created by the explosion. I have touched the remains of the steel and concrete tower stubs. It's a humbling experience to stand where humanity's history changes forever in an instant. I spoke to an old gentleman there, who was a soldier and witnessed the blast. He had an interesting story that a family was driving on a highway, north of the area, towards Albuquerque. They had a blind daughter in the back seat who woke up at the instant of the explosion and asked her parents if the sun had come up because she just 'saw' a bright light.....only explanation was it probably xray/gamma burst that had stimulated her optic nerves.....
I al ways dreamed of visiting the Trinity site, the closest that I got was visiting Los Alamos when I was a PhD student
This would make a great modern day mythbusters skit.
X-rays/gamma rays stimulating your optic nerve is a real thing. Astronauts have reported occasionally seeing bright flashes when their eyes are shut, indicating a cosmic ray has hit their optic nerve. This phenomenon has been reported by astronauts going back to the Mercury program.
No, that is impossible. Gamma and x-rays don't travel that far in air. It's a myth that is being recycled over and over again.
...an interesting story! 🤔
84 years in Phoenix AZ here. I recall witnessing 2 or 3 Nevada tests (~340 miles). I believe they all occurred just before sunup (sky not dark). My recollection is that the "flash" was of very short duration, similar to a photographer's strobe light. Bright white sky, horizon to horizon, but for only the smallest possible amount of time.
On a more mundane level, the physicist Richard Feynman was present but hadn't been provided with welders goggles like everybody else. So he closed his eyes and put his hands firmly over his eyes. He said that when the bomb exploded, he could see the bones of his hands clearly as if he was looking at an x-ray, that's how bright it was.
I’ve read several times that because he knew glass is opaque to ultra-violet (knowing obviously that the blast would generate intense ultra-violet) he sat in a truck cab and observed through the windshield. Maybe he also shielded his eyes with his hand.
I doubt he wasn’t given the option of welder’s goggles.
@@bogeycrow1968 But glass is not opaque to uv
@@bogeycrow1968 In his book he implies he wasn't actually invited (but went anyway) and there weren't enough goggles for everybody! He was a practical joker and always bending the rules, including opening locked filing cabinets and safe boxes. His story might be exaggerated.
@@bogeycrow1968 Yes, that's what he says in his book. Glass doesn't block it to that degree, however, if the intensity outside is really high. I'm sure he did put his hands over his eyes, he knew roughly what was coming!
I don't know how the algorithm got me here but your science, your clean editing and the no-nonsense, informative presentation of your video got me to stay. Please keep doing this!
thanks for the positive feedback, more videos coming soon
you are totally right!!
Yep. This earned a sub from me!
The first time I saw that video of Oppenehimer, which was many years ago, I assumed right away that he was identifying with the warrior, maybe because I have the cultural background. Actually, the warrior's dilemma (and by extension, the human dilemma) is what the whole Bhagavad Gita is about. Thanks for an interesting video. 👍
The Bhagavad-Gita is a fantastic book,the essence of what spirituality is about !!!
H
It’s a great line to understand if said with a sense of wry, semi-sarcasm (paraphrased) when thinking of one’s _duty_ to do something destructive…”Oh, great, now I’m a destroyer of worlds.”
Anyone who mentions Iron Maiden during a scientific discussion automatically gets my sub.
Thanks for watching and subscribing, and welcome to the channel!
I know nothing about atomic blasts but a little re. daylighting. Your estimate of 50% of solar radiation being in the visible range is very good. The measured value at the surface of the Earth is 42-43%. I expect the percentage to be lower for extraterrestrial solar radiation as the atmosphere absorbs more selectively in the UV and IR bands.
The percentage of luminous energy in an atomic flash will however be lower than that of sunlight. The solar spectrum peaks right in the middle of the visible band thanks to the temperature of the sun's surface being ca. 5700K. I suppose an atomic flash peaks well outside the visible spectrum.
Thank you for producing such a high quality content, Dr. Diaz.
Much appreciated! Thanks for watching and subscribing, and welcome to the channel! I hope you also have a look at the other videos. Comments, questions, and requests are more than welcome.
10 Suns would still be a terribly impressive thing to witness, but the poetry (and Gita tie-in) of the "thousand" is undeniable. I'd just been made aware of the other interpretation of "Now I am become Death...", and appreciated your explanation. I can't help thinking that Bainbridge's words are less open to interpretation: "Now we are all sons of bitches", which apparently Oppenheimer quite liked!
If the fraction of the total energy output that goes into the brightness/flux is constant, you "only" need a 2Mt bomb to get 1000 suns. That has been easily surpassed by thermonuclear tests. 7.5 times in Castle Bravo, and 29 times by the Tsar Bomba.
thanks for the comment, I am glad you found the information of interest. Bainbridge's quote is a classic.
And there isn't much of a subjective difference between 10 and 1000 suns - the world just turns completely white for you regardless.
Most polynomials tested the toncisticity of my decanter of Scotch whiskey. That's a lot of jewels.
The band "Rush" has a title called "Manhattan Project" on their power windows album.
The song mentions a light brighter than the rising sun and an August day.
A good balled.
thanks for sharing this, I had no idea; I looked it up and the lyrics even contains a reference to the Hiroshima bombing "The pilot of Enola Gay
Flying out of the shock wave," which the topic of my first video ruclips.net/video/IEsIXui-YS8/видео.html
Prefer the Show Of Hands version. 🤪
@@MichaelBoltonsEntireCatalog there is another rendition of the "Manhattan project" by "show of hands"?
~10 suns! I love the power of estimation, especially with physics.
Dr. Diaz (this may be pedantic) do you think ~50% was a good approximation for the amount of visible light? I was expecting almost an order of magnitude smaller. I don't have good intuition for at least two parts of the explosion, the distribution of frequencies of light produced and the amount of light converted to visible later on.
I would've guessed the amount of initial visible light produced would be ~5-10% but I don't have a good intuition about this.
I imagine a huge amount of gamma and x rays produced. This light would be absorbed and reemitted (through Compton scattering?) at lower frequency (repeatedly) causing the air to glow further. I don't know how much this would convert but I think we can assume the air to be a black body radiator (for which the frequency curve is centered near the visible light frequencies). This sounds like it could convert another 5-20% (total guess)?
Sorry for the long response but I would love to hear what you think Dr. Diaz.
pedantic comments are more than welcome! I honestly didn't try to get an exact estimate but just an order of magnitude; for this, I used the standard of 35% of the energy in the form of thermal radiation and then, on top of that, I took at 50% for visible radiation, this gives ~18% of the energy in the form of visible light. Therefore, I might be off by a factor 2, but for an order-of-magnitude estimate this is just ~1 :) The main point is that 1,000 suns appears to be just a literary license.
this is a brillant video and one of a few with real science envolved, thanks
thanks for the positive feedback, more videos coming soon so keep an eye on this space.
RUclips is wild sometimes. Getting educated by physicists for free? Yes please.
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@@jkzero oh I did
It's incredible to think humans actually did this and the fusion bombs which followed. Quite literally the power of a star being released on the surface of the earth. It must have been incredible and terrifying to watch one of these things in real life. I would love to have seen the Castle Bravo and Tsar Bomba tests from a safe distance!
I suspect that "1000 suns" isn't that far off for an H-bomb, whose yields are typically measured in mega-tons rather than the (now so quaint) kilo-tons 😞 !!!
when you go from nuclear to thermonuclear weapons to are taking the yield about three orders of magnitude, that's insane
Thank you for this video. Important context to get the interpretation of Oppenheimer's words right.
It was said that a blind girl, I think that her name was Georgia Greene, who was riding a a car at least 50 miles away from the explosion, sctually saw the flash of light, pointed in its direction, and asked "what was that?".
I recall the story of the blind young lady, but I don't know whether it is true or part of the folklore around the Trinity test.
It's true. Google Georgia Greene.
It's true. Google "Georgia Greene Trinity test"@@jkzero
I don't think there's any mistranslation or misinterpreting he knows exactly the bomb he created has the potential to end humanity and the planet he means it exactly as said he has become the destroyer of worlds in that moment
I fully agree that Oppenheimer knew exactly what the power of the bomb was and how it would be used, there is no doubt about that, despite the image projected of his naivete in recent films. I have no intention of cleaning his image or role. I appreciate the comment and I respect the opinion, but in the full quote Oppenheimer ends with "I suppose we all thought that one way or another" so despite Oppenheimer's well-know arrogance, there is a lot of room for interpretation.
Excellent calculation estimate. One thing that basically every media depiction of atomic weapons do is show these detonations as huge blasts of napalm. Nolan did a really bad job in the "Oppenheimer" where he displayed it with yellow-orange color.
These detonations are so hot and so bright that they are essentially plasma for well over a second, and they glow violet-blue-white. The greater the weapon yield, the worse it gets. There are old test videos where detonations look red, but that's a combination of photographic filters which were not neutrally dense, but more like welding goggles, and decay of photographic film.
In reality, the sight of it was profoundly scary and, as Oppenheimer said, most stood silent, shocked by the energy they've helped release. Nothing like in the film where people clapped and cheered. Nolan really had a nice opportunity to do it properly, but he made many bad choices.
As a person watching footage of nuclear explosion since I can remember and after all the hype about Nolan's depiction of the Trinity test I was so disappointed with the final result, clearly Nolan fired up a truck full of gasoline and thought that we would all buy it. I liked the film and I loved the building up to t=0 but the explosion was pathetic. It was almost as terrible as the depiction in "Fat Man and Little Boy" with that leaf blower over Oppie's face.
@@jkzero Yes, and even considering it was a form of biography, and even without personal expectations of the film going into technical details (I assumed it was going to be about his life and turmoils), I was still so disappointed when the main event came. Nolan was creative with usage of liquid suspension of mica, but the sluggishness of it and the dull, fiery color was a cold shower. It did not bring up the terror of apes unleashing something they can not control.
@@lajoswinkler the nuclear test in Twin Peaks was orders of magnitude more terrifying than Nolan's disappointing depiction
I enjoyed the calculation part very much. Beautiful presentation! Thank you for finally getting the answer: 10 suns! Love it.
But when it comes to Oppie and the Gita, there are many problems. Ryder mistranslated the Gita -- and caused Oppie in turn to misquote the classic? Maybe, but that shouldn't be, since Oppie claimed to have "learned Sanskrit from a professor at U.C. Berkeley." Anyway, the snippet translated from 11:32 is simply wrong. The line is "Time I am" [kalah asmi], not "Death am I." (Out of the half-dozen translations I've seen, only Ryder mistranslates 'Time' [kalah] as 'Death'. WTF? This in turn means he misunderstands the whole 'story' but that's too messy to unravel here.) Also, Hijiya's monograph is slanted, verging on a puff-piece: According to him, there was only [1] science and [2] politics to worry about. What happened to [3] ETHICS and [4] war crimes? This business of Oppie's about "I let the adults in the White House decide those things" has always irked me. Oppie arrogantly buried a petition (mentioned on page 138, btw, as seen in the video @10:52 in the unhighlighted section) in which everyone EXCEPT him definitely had a no-civilians opinion, and did not see "us scientists as little people in the White House who should remain quiet like children at the children's table and not interfere with the adults" (I paraphrase, obviously). Oppie was a war criminal, and I'm sick of seeing all this adulation of him. (Also, John von Neumann was WAY smarter than Oppie and without von Neumann there would have been no bomb.)
The solar flux in outer space is about 1.34 kW/m^2. But the atmosphere absorbs a substantial fraction of that. At noon, at the Equator, with no cloud cover, you have about 1 kW/m^2. So it's more like about 6 to 7 Suns.
Still, during the whole event, the intensity varies greatly from one fraction of a second to the next. The first of the two flashes, which occur in very quick succession, may be much more intense than those figures, BUT it's VERY brief, and the human vision system averages over some interval, some fraction of a second, so that subjectively, it will not be as bright as the maximum instantaneous value.
Oh, and the color spectra are different for the Sun and the Trinity blast.
In other words, to fully answer this question, you need a deeper analysis.
thanks for the extra details, you are right: a precise result requires this an many other details to be consider. I was mostly interested in an estimate of the order of magnitude instead of an exact value. In fact, some measurements show the first peak to reach "~80 suns" for a few milliseconds.
Correct as far as the actual intensity at the surface of the Earth at sea level when the Sun is 90 degrees above the horizon without clouds, but the resultant number of Suns would be more like 14 (14kW/m^2 / 1kW/m^2).
I wouldn't use solar constant as a reference point because it uses how much energy Earth receives in a vacuum. On Earth, even on clear midday the atmosphere acts like an ocean and we sit at the bottom of it. So we receive close to a third, even in tropical regions of what we could in low earth orbit, which is about 350 watts per square meter. It greatly reduces the efficiency of solar panels on the surface compared to low earth orbit.
Thanks for this, you make a very good point. It didn't occur to me to weight the atmospheric reduction on the solar constant. Using your estimate, if the solar constant is reduced by a factor 4, then instead of ~10 sun you would get ~40 suns for the brightness of the Trinity test. Thanks again, very good detail.
Wow, its even more tragic when given more context of the literature. Ultimately just like Mordin in Mass Effect 3 he had to be the one to do it. Otherwise someone else might have gotten it wrong. Very very wrong
It is true that over 1 second the fireball released enough energy to be comparable to 10 suns, but the reaction is over in a few microseconds. That means the same energy would be released in that few microseconds. That momentary flux was millions that of the sun.
11:02 It's not that others were more qualified to make political or war decisions, nor that he didn't make those decisions. By making the bomb, he *was* deciding.
Nor should people "honor" their elders by submitting to wrong decisions. If a decision is wrong, it doesn't matter that an elder made it. It's still wrong, and should be opposed.
The calculations here are not very waterproof.
1. The estimation, that the energy was released constantly within 2 seconds is too rough guess. In reality, 80-90% of the energy is released within the first microsecond. Therefore, the maximum brightness might also be 2000 times brighter than the average brightness of first 2 seconds.
I don't think eye witnesses refer to the fireball when they are speaking about the brightness of nuclear explosion. They are talking about the flash.
2. You use the strength of visible light in your calculations. However, the solar constant includes all the ultraviolet and heat radiation also. Less than half is visible light.
3. Solar constant is only ~1000w when measured on the surface of the Earth. 1300W is only in space, where there is no atmosphere.
4. Brightness is a bit wonky term, because some might argue that the brightness of explosion doesn't lower, when the distance grows. It only gets smaller. Luminosity would be more precise term. However, in stellar objects, brightness is used as a term in this weird way, I grant you that.
And only about 15% of the P239 actually fissioned. A 6 kilo hollow ball lit up the sky like a blazing apocalypse.
How bright was it, blind fold your face, then cover your eyes with your hands
You'll still see the bones and veins in your body like and x-ray an still hurt and blind your eyes depending where you are
Feel like a sun at noon
I remember reading somewhere about a young lady, blind from birth (I think it may have been the case that she didn't even _have_ optic nerves, but I wouldn't swear to it) who was a passenger in a car some 40 or so miles from the blast, I believe (again, iirc - 40 miles _does_ seem a little close for comfort!) Anyway, she SAW the blast. It was the one thing she ever _did_ see in her whole life. As such I would contend that unless one belongs in the more rarefied strata of the physics community, arguing about whether, and how much, the "Light of a Thousand Suns" comments were exaggerated seem rather like a case of 'splitting hairs', even if it was a question of orders of magnitude! Particularly so if the observers cited were as well read as their boss, and they were referencing the holy books. Even if not, one suspects that rather than trying merely to be literally accurate, they were trying to get across a 'deeper' truth. (Given the total nature of the lady's blindness, I suppose the 'light' she saw might well have been 'all up and down' the E~M spectrum. Probably that's mostly a medical question. Again, though -- nit~picking!)
As for Oppenheimer's famous quote in the 1965 NBC documentary, I admit I always assumed he was being a bit 'grandiose' - although if ever there was a case of grandiosity being justified, this was surely it! If Willardstein and Ihia (spelling?) are correct though, and they very likely are, given that his words were surely edited at least somewhat for the NBC special, never mind the thousands of times we've seen that clip since, it seems like - along with everyone else on the planet, more or less - I failed to ascribe to the man's words the nuance they deserved.
Anyway, some interesting nuggets here for physicists and historians both, I should think. Certainly, as a layman I found it interesting and revealing - nice little documentary. Thank You, well done!
I also recall the story of the blind young lady, I don't know whether it is true or part of the folklore around the Trinity test. I think you are right that analyzing literal comments/quotes quickly becomes splitting hairs, I do not intend to do that but rather use them as an excuse to get to talk about physics and topics that I find interesting.
Regarding Oppenheimer's quote, there is no evidence or report of Oppenheimer's saying it or thinking about it after Trinity despite having a journalist (W.L. Laurence) on site, except the NBC recording 20 years after the event. I am inclined to consider this a case of false memory.
@@jkzero I suppose, if you'll forgive me stating the obvious, we can never _really_ know what somebody is thinking in their mind, and though I haven't read any of the biographies on JRH, I think it's probably not giving him, though a scientist, too much credit necessarily to think he would be conversant with the Bhagavad-Gita. Also, while in any other circumstances, to employ those particular lines might come across as just a little portentous (not to mention _pretentious!_ ) on that particular occasion, they _do_ seem particularly apposite, whichever light one may wish to read them in... if anything, one might say the passage was almost a little _too_ apposite, _too_ perfect to just come to mind to him at that moment! Even had he previously given some thought to something that might be appropriate for the moment, given, as you say, the presence of W.L. Lawrence, one might have assumed that that was the perfect moment to record the thought for posterity... I think it may not be _100%_ correct to say that in 1965 he was misremembering his thoughts in the moment, but certainly at the time of the interview he'd had the benefit of 20 years to structure and hone his impressions... It may well be that the key part is where, after the bit about "... Becoming Death, the Destroyer of Worlds", he kind of tails off saying "I suppose _we all thought that, in one way or another..."_ So - by no means a lie, but it does illustrate the process by which a more or less unformed impression can, over time, become the quote that defines a man. And yes, having first practically wrote an essay bemoaning the splitting of hairs, I had to go and top it by deconstructing a quote upon which, no doubt, whole theses have been written...
I do wish I could remember who it was amongst those present on that morning - it may even have been Oppenheimer himself - who admitted something like "What did I _really_ think? Actually, I think, like everyone, I just thought 'Well - It Works -- Thank God!' "
@richiehoyt8487 Sometimes a little nit-picking is good for the discussion
I have always thought the blind woman story was false. If you are blind you are blind. Even if she was suddenly gifted a split second of sight she wouldn't know how to describe it because she had never seen anything to begin with.
well if you remember reading something, someplace, at some point, who are we to question that and not take it for absolute fact. Thank you so little for sharing that tidbit we need a lot more speculation, 5th hand guesstimations, and pure make believe
My grandmother once told me many years ago how they were testing these in southern Nevada in the early 50s. She told me a story about when she lived in San Diego at that time, went outside around 5am to get the newspaper, when it was still dark. Suddenly the whole sky lit up for a few seconds, and the sky had a weird red glow for a few minutes after. She knew it was an A bomb test in Nevada. Said it scared her so bad she went back inside and didn’t come out for the rest of the day. The fact that it lit up the sky that far away is insane.
Thanks for sharing such a fascinating story. As a kid I had the recurrent dream of witnessing the Trinity test. It was always terrifying but somehow beautiful at the same time.
...I wish I could have asked him about that experience.
I really feel bad for Oppenheimer. This task of his destroyed him.
The thumbnail looks like the shape of the old Civil Defense helmets.
My grandfather remembers the newspaper said it was an ammo depot that exploded. My family lives really close
wow, that's such a story! Yeah, that was the cover-up story for the day after Trinity. I hope your family was not affected by the fallout; many communities were affected
I wonder how well we could light up a shadowed part of the moon, seen from earth, with one explosion. Edit; exploded on earth if not bit higher up
I did the calculation many years ago, I would need to recall the details, but if my mind doesn't fail me, the answer is that for an observer on the Moon, the Trinity test would appear as bright as Venus in the dark sky. Is that sufficient to cast a shadow? I believe not.
@@jkzero hmm so we’d never be able to direct a flash from any source off planet above us. Only our satellites looking for double “rainbow” (flash) straight down can detect then huh.
@@erdngtn9942 I am afraid so
@@jkzero thanks big guy (or mam but pretty sure voice matches channel owner, yes?) but thank you kindly. So interesting. No bs filler in your stuff.
@@erdngtn9942 guy, but quite short. Thanks, I am glad you like the content.
I like this interpretation because I don't like when people hold oppy responsible for the existence of nuclear weapons. Like they wouldn't have been developed without him.
I fully agree with this
To get pedantic the luminosity of 10 suns is true at 10 miles / 16km. Closer in it would have been higher. If my math is correct then at a distance of 1 mile / 1.6km the "illumination of one thousand suns" would be true. Not quite sure if this would be a survivable distance from the detonation though either from thermal or blast effects.
I am big fan of pedantry, so happy to get this. You are totally right; however, I would assume that one (Oppenheimer or any other witness) observes such an event, the reference is the observation point and not how the event would look like somewhere else. Otherwise, almost any bright object could be "brighter than a thousand suns" by choosing the appropriate distance.
Thanks for the very enlightening and informative video!
Can you imagine? 9cm of material.
See the light; Feel the heat. -- Ronald Reagan
Cool video. Brilliant narration
Glad you enjoyed it. More coming soon.
The trinity test was so "bright" Feynman watched it without protective eyewear by using the windshield of a pickup truck to block UVA and as close as anyone could get to the detonation.
en.wikipedia.org/wiki/Trinity_(nuclear_test)#CITEREFFeynman1985
I have read several accounts for things that Feynman did at Los Alamos and Trinity. Feynman was a great physicist and a fantastic educator; however, when it comes to his shenanigans I take them with a grain of salt. I don't say they didn't happen, but if you read "Surely You're Joking, Mr. Feynman!" you can tell that he tried to generate this mystique around him.
@@jkzero gospel.
Another way to put it is considering the inverse square law, which applies to radiant electromagnetic energy. This law states that the surface power density disminishes in an inversely proportional fashion relative to the distance from the radiant source. Thus, at twice the distance, we get one fourth (25%) of the power density, and so on.
The so-called solar constant, with its 1.4 kilowatt per square meter value, applies to the vacuum in space surrounding Planet Earth, located at an approximate distance of 150 million kilometers. Therefore, in order to get a 14 kilowatt per square meter power density - such as emitted by the Trinity flash - the distance from the Sun should be 150 million kilometers multiplied by the reciprocal of the square root of 10; that is:
150 x 10^6 x 0.3162 = 47.43 million kilometers.
Mercury, the closest planet to the Sun in the Solar System is located at 58 million kilometers from the Sun, whose surface temperature is around 427 degrees Celsius. In turns, this leads me to estimate that, at the 47 million kilometer mark, that temperature could very well be close to some 500 degrees,
Notwithstanding, the flash from Trinity was an ultrashort pulse, a few microseconds long. However, a sustained emission of 14 kilowatt per square meter could very well manage to induce an ambient temperature rise to 500 degrees, virtually roasting everyone around, even at a location ten miles distant from ground zero.
This fact became readily apparent to the people present at the Castle Bravo Thermonuclear 15 megaton test at Bikini Atoll on March 1st, 1954. Although stationed on the deck of an aircraft carrier, distant some 32 miles from the blast, the general complaint centered on the tremendous, unabated heat, almost as if being subjected to the influence of a blow torch (!!!)
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Regarding the fraction of visible light contained in the radiated energy by the flash, I guess the Planck Distribution for an incandescent source could possibly prove to be a most valuable aid in providing an acceptable estimate.
14kw/m2? Maxing out my MAG welder gives me an output of roughly 7kw. Concentrated on a tiny point, about 1 cm2.
If I understand the calculation correctly, it is highly dependent upon the distance: perceived brightness is inversely proportional to the square of the distance from the explosion, such that at 19 miles (3.16x as far), the perceived brightness would have been equivalent to the sun.
Similarly, a 1 MT explosion would, according to the same set of calculations, be 50x as bright from the same distance, though I hope no one would set up observers so close to that sort of test; presumably observers could be 7x as far away and get a proportional effect.
When I was an undergraduate, the head of the physics department at NCSU L. Worth Seagondollar was a nuclear physicist. When he was a graduate student, he got to work at Los Alamos on the bomb project. I heard him lecture on his experiences several times. It was enthralling. One point he always made was how incredibly bright the explosion was and how videos and pictures really could not capture this effectively.
A week or so before the Trinity test, there was a lecture on safety procedures. At one point, an ophthalmologist gave his presentation on eye protection. The speaker wryly observed that if the bomb was 10 times less powerful that they estimated, there wouldn't be anything to worry about because the light would be too dim to hurt them. If the bomb was 10 times more powerful than their estimates, they wouldn't have anything to worry about then, either -- because dead people don't need to see. But if the bomb was about as powerful as they thought it was going to be and you didn't have eye protection, you might go permanently blind.
The grad students had planned to use standard welder's goggles to protect their eyes. "The more the ophthalmologist talked, the clearer those glasses looked," my professor recalled. They decided to use a piece of electric arc welder's glass mounted on a piece of cardboard. In the attached video, Seagondollar explains what happened during the test. It's quite a story!
ruclips.net/video/AsYGSqSzWcA/видео.htmlsi=yLjiyO4VOXkfOnp2
The 1000 thousand suns brigthness will be consistent while being at a distance of 914 meters, instead of the 9140 m of the stationed observers.
Oppenheimer was an interesting & COMPLEX guy. Also, I vaguely remember Teller (?) talking about holding up "welder's glasses" to view the blast which reminded me of taking shop class & having to learn arc welding in Junior High & wearing a helmut so is the light from arc welding on par with a nuclear blast?
Re the cartoon at 0:55 If you make a scale model where a nucleus is the size of a basket ball and a neutron is a ⛳️ ball, the atoms are about one mile apart, and the pit extends to jupiters orbits.
Moral of the story: nuclei are much smaller than atoms and Avogadros number is really, really, big.
I agree with your assessment of Oppenheimer's words and his role. This video was presented very nicely and straightforward science. Your guesstimates appear better than many folk's claims of a more precise analysis. Observation and experience matters, eh? Great job, Doc, of laying it out for us lay persons.
Just discovered your channel, and you don't have a clue of how much success this channel will achieve in the next months/years. Top quality content, straight to the point with the right technical informations. Keep up🎉 BTW, just a curiosity of mine: from which country are you from? Cheers from Brazil!
thanks for your words, I appreciate the positive feedback. I just find amazing that other people find these topics of interest too. I want to make videos that are technical but without going into hardcore math so everyone can enjoy them. I am originally from Chile, although it has been many years that I left my home country. Greetings from Germany.
very interesting
3:50 If I had read that report in 1977 I would not have understood what it meant. But now. Wowow. 35% thermal
Thank you for your work. I really like your videos! Greetings from germany.
Thanks, I am glad you liked the video. I am always curious to know what brings viewers to the channel, were you searching for something in particular or did the 'mighty algorithm' find you?
@@jkzero I searched for the enola gay just because i was interested in it and found your channel :)
@@LukasHerrKompetenz Thanks for sharing and I am glad the search algorithm brought you here, I hope you find the other videos of interest too and welcome to the channel.
The light is so bright that it can instantly ignite everything flamable at close range and give 3rd degree burns to all exposed skin at medium range.
The military personnel were 16 km from ground zero, and the scientific observers were 10,000 yards is an odd choice of units. Basically 16 km and 9 km. Almost like it was taken directly from google 😂
The military personnel were at the base camp 10 miles (16 km) from ground zero, and the scientific observers were 10,000 yards; those are the units on the official declassified reports of the Trinity test. I do not "take things directly from google."
The brightness of the fireball would also be inversely proportional to the solid angle subtended by it from the distance of observation. If it was smaller than the disk of the sun, then it would be proportionately more intensely bright. Also, the Solar Constant of 1360 W/m2 is measures at the top of the atmosphere, and is observed less at the ground due to atmospheric attenuation and angle of incidence.
You are totally right there, the brightness depends on the distance to the observer; however, in this case my interest was how bright the Trinity test was for Oppenheimer and the other at the observation bunker. You make a very good point about the solar constant, it didn't occur to me to weight the atmospheric reduction on the solar constant. Using the estimate of an average close to 350, if the solar constant is reduced by a factor 4, then instead of ~10 sun you would get ~40 suns for the brightness of the Trinity test. Thanks again, very good detail.
I worked in the photonics arena for over a decade, as well as photography and photoscience. It was interesting to see the calculations of the flux of visual energy. I also write what I call philosophic poetry, and seeing the Hindu text behind Oppenheimer's famous quote, was very interesting to me.
I am glad you found the content of interest, make sure to check the other videos, I am currently running a video series on the early developments of quantum mechanics
As a filmmaker, I cannot stress enough how weird it is to hear that something is brighter than the sun, let alone 10 times. Most people don't appreciate how insanely bright the sun is. Nothing competes with the sun.
Thanks for stopping by and watching. As a filmmaker, you might find of interest that before the Trinity test scientists didn't know how bright it would get so they prepared dozens of cameras covering a wide rage of settings. In most cases, the film was overexposed and plain burned. After the Trinity test, rapatronic photography was developed to properly capture the early moments of nuclear explosions.
👏🏻👏🏻👏🏻🍻🇿🇦
Comparing this numerical value to that of the sun, as shown here, does not take into account that the sun is 93M miles distant, while 10k yards isn't even 6 miles.
I guess the title should be "How bright was the Trinity test from the point of view of Oppenheimer and colleagues at the observing bunker"
Kinda interesting military personel was 16km from the gadget and scientists 10.000 yards, told in same sentence. But great great video ! 😁
The military personnel were at the base camp 10 miles (16 km) from ground zero, and the scientific observers were 10,000 yards; those are the units on the official declassified reports of the Trinity test. You can even found the official maps using these mixed units.
The perception of brightness by observers must have been affected by how the explosion illuminated the mountains and surrounding landscapes, perhaps more than the bright explosion itself.
you are probably right, most of the eyewitnesses reported that they could not see much through the googles and protective gear provided and many simply looked at the mountains rather than the Trinity tower
If he didn't do it 10 others were in line to do it!
Thanks for the explanation on Oppenheimer's statement. I've always been confused as I never really believed that he meant it how it's portrayed.
Glad it was helpful! For years I found the quote confusing and then seen it misused everywhere led me to make this video. Thanks for watching, I am glad my early videos still get views. I ran this series on nuclear weapons last year, I am now running a video series on quantum physics, in case you want to check it out: ruclips.net/p/PL_UV-wQj1lvVxch-RPQIUOHX88eeNGzVH
All this destruction power all from a rock that weighted about as much as a butterflies wings
Uranium and Plutonium are the closest that physics has taken us to "magic rocks"
You found something closer to the truth and showed it to us. Thank you for helping clear up this misinterpretation of such a popular quote.
This subscription was such an easy decision - no asking needed.
Thanks for watching and subscribing, and welcome to the channel!
A well put together infomentary.
Nice to see a scientific estimate of the amount of (visible) light energy emitted. It's going to feel a bit warm at that distance if you include the infrared radiation. I wonder if it would be safe to set up 20 mirrors, all reflecting the sun onto the same place, then run through the reflection (wearing eye safety glasses) to get a rough idea how it might feel. At 9km distance, it is a surprising amount of energy still.
Get enough photons of all energy levels concentrated.....
Woooohhh Baby!
@@caleroby9483 There is actually a test range that uses sunlight to simulate nuclear light exposure. It seems much more than 20 suns though. There are videos of it almost instantly igniting a tree on the test stand. That is a large scale testing rig. No need to bother with the mirrors if you want to try it, just concentrate sunlight with a magnifier until the power per square cm is the same, then put a hand under it briefly to test. Much safer with the much smaller possible damage area and a lot less risk to your vision. Could swear I've tried it as a child and didn't feel too much discomfort until the spot got really small. Light coloured clothing (or any) at that power level, and for the brief amount of time would be good enough protection - as observed in the test footage with the soldiers about 20 miles away from a 1Mt test.
I am so going to out-nerd people with this. Thank you for your work!
Nice; make sure to check the rest of the playlist on nuclear weapons and have a look at the running video series on quantum mechanics, it comes loaded with stories that can help outsmart even many physicists who have been thought erroneous narratives and even incorrect stories.
Don't be upset knowing that Trinity was "just" 10 times brighter than the Sun. 9 yeras later Castle Bravo fixed the situation.
ouch
Visible light is a small part of the spectrum. I’d suggest it didn’t even get to 10x brighter than the sun? Don’t forget those who viewed the nuke were 93 million miles closer to the flash than that sun.
J. Robert Oppenheimer, and to a slightly lesser degree his brother, got such a bad deal. I so would have loved to have just met either one of them, much less to have serious discussions or to have J. Robert Oppenheimer as an advisor/mentor while I studied physics. The world would have been a much better place if we had only listened to him and those like him.
I never assumed that Oppenheimer was referring to himself. That's an extremely narcissistic interpretation.
It is, however, the interpretation pushed by every single documentary that you can find around
@@jkzero Didn’t President Truman kick him out of his office? Starting to make sense. He was brilliant, but ….
The synchronicity is exceedingly intriguing! I have been working on the answer since 1969, the one Halley, Newton, and Whiston introduced to science, by asking the right question to a very learned man at the correct time. Nobody understood the quote, and still don't, yet....... I know what Oppenheimer was taking about! The best example is to compare the Blinding Bright White Light of the ablating 2013 Superbolide footage, from below, followed by Two counter-rotating smoking vortices to the Two Chinese New Year Dragons that chase a Bright White Pearl, accompanied with Fireworks. The Omnipotent of essentially every Worldwide Tradition is from The Pleiades, the radiant of The Taurid Meteor Stream, our most recent. It is shown symbolically in Lascaux Cave Art, Gobekli Tepe, Tauroctony, and our children still carry on the exact same tradition, at the exact same time, going around asking strangers if it will be a bad or good outcome when crossing The Halloween Fireballs - The Taurids! We are at an equally crucial moment and ALL of us need to fully understand this concept, as there is sympathetic magic of debauchery to propitiate The End of The World - The Younger Dryas Impacts Theory / Fact and the lesser Burckle Crater Mega Tsunami as a misguided notion of transcendence. The message is saturated everywhere; from the weathercock, the seven spikes of the diadem on The Statue of Liberty, to The Aldebaran Colored Heifer! I compiled and published a compendium that proves it without doubt and have concluded that we carry a genetic memory of the horrifying traumas of our cyclic world of destruction, impact winter, clearing of the atmosphere, then renewal of life by knee jerking into denial and change the subject or scoff without rebuttal. We Anthropomorphized inner solar system space debris and its accretion into our reality, or lack of. The Superbolide phenomena have greater yields than our best, do they reach the thousand Suns mark?
Somos nuestras decisiones y acciones. Jamás será un mártir ni alguien que hizo "lo necesario", un mal necesario. Claramente, solo fue un mal y una verdadera lástima con tan brillante mente prestarse para ello. Por supuesto hubiera sido otro pero creo que pudo disuadir a las mejores mentes de su época a no participar en esta clase de proyectos así como los persuadió de hacerlo. Esa clase de física no tiene nada de "bonita" ni elegante.
Gracias por el comentario. Se respeta la opinión, sin embargo sólo quería clarificar que en el video nunca intento justificar las acciones de Oppenheimer y otros, simplemente aclarar una frase mal interpretada.
The steel tower was not vaporised at the trinity test bits of it were examined afterwards at one point a rocket scientist investigating potential use of explosives to launch rockets examined parts of the tower to see how the steel held up against the blast, the tower’s steel was warped and mangled but had not “evaporated”
This is news to me, I have clearly followed the standard narrative of the vaporization of the steel tower. Do you have any reference for this? Could you please share it? I am really curious to know more about this. Thanks!
@@jkzeroLook up Project Orion, where US scientists, including Freeman Dyson, studied using small nuclear bombs (under 1kt) to propel spacecraft, including launching them from Earth. It would have been a Pulse Engine, driven by a series of nuclear explosions. I recall reading that during the Trinity test, a round metal plate was propelled (I believe it was upward) but suffered little damage, except for some ablating. This led to the idea of using a pusher plate that would absorb the energy from the nuclear explosions, but would not be destroyed. The Orion team, which worked on this project in the 1950s, postulated that they could have a spacecraft visit Saturn by 1967!
A calculated 10 suns brightness at the point of detonation is about equal to 1000 suns at the distance of the sun. Perhaps that makes sense?
That might a clever interpretation; however, I doubt (just my personal opinion) that a person observes something bright and describes it as "how would this look at distance from the Sun," most likely it would compared to the Sun at that point.
Ten suns brightness at ten kilometres distance…
Next time I get my genie out of the bottle, I know what I will wish for: a 90000000000000000 lumen LED flashlight.
that's brilliant
I like this interpretation.
You can give a rough estimate pretty fast. A 300 m fireball at 10 km is about 25× bigger than the Sun -> 25× brighter. OFC the surface temperature was less.
It appears that you are just comparing the angular size of the Sun to a fireball at a given time; however, I would argue that angular size is not enough and the energy flux is crucial. Take for instance the Moon: it has the same angular size as the Sun (~0.5°); however, you would not say that "the Moon is as bright as the Sun."
Also, for a fireball of 300 meters in diameter located at 10 km I estimate the angular size of ~1.719°, which is a bit over 3 times the angular size of the Sun, so could you please elaborate where the "300 m fireball at 10 km is about 25× bigger than the Sun" comes from?
@@jkzero I used nukemap, which gives about 290 m radius for a surface shot, which translates to a 400 m diameter circle, the bunker was at 9100 m, which gives us a 1/22.75 ratio, the same ratio is 1/108 for the Sun. The square of these two ratios divided is ~ 22.5. So it looks like that the surface of the fireball was about 1/2 of Sun's surface brightness.
Take a 1980s bulb flashlight and compare it to a modern LED flashlight with a smaller lens size. The LED flashlight with the smaller lens size is just brighter. The angular size of the fireball doesn't matter. It's the amount of visible light that gets emitted and the distance to it that matters.
This is amazing.
good job on this.
Done❤
Thank
I love this series of videos! Thanks!
Glad you like the videos; I am currently running a video series on quantum mechanics, in case you are interested check the playlist
14 kW/m2 | 1.4 kw /m2
= Bright AF
giggity
I have fallen in love with this channel after three amazing videos on physics (that I watch so far)!
Happy to hear that! Enjoy the other posted videos too and more coming soon. Thanks for watching and welcome to the channel! Curious to know how you found it, were you looking for something in particular?
@@jkzeroI was actually just scrolling through my homepage before I ate dinner so I had something to watch when I was eating. I found the video on “The math behind saving the enola gay” really interesting and clicked on it, and was anything but disappointed. I watched the whole thing, then kept watching more videos even before I went to sleep lol. Right now, I came back to rewatch this one, because I watched this one right before bed and didn’t fully process it.
@@Asterism_Desmos thanks for sharing how you got here and for binge-watching the channel. I am glad you found the content of interest, I cannot guarantee to take all requests but I am collecting suggestions, if there is any particular topic you are curious just let me know in the comments. More videos coming soon so stay tuned.
@@jkzero So far, I think the real world examples of how math and physics can be applied could be cool. And nuclear physics is always an interesting topic. Really, you’ve done amazing at choosing topics so far, so keep up the good work!
@@Asterism_Desmosthanks again for the positive feedback!
How bright is was is a matter of how close you were
True, I guess a more complete title for the video would be "How bright was the Trinity test when compared to how the Sun looks in the sky at noon" but that would be a bit too long.
@@jkzero again, how far from the blast stands you?
Has anybody seen an explanation of by how much the plutonium core was compressed in the Trinity/Nagasaki explosions. Would the compression of the core during detonation be visible to the naked eye?
A quick Google search says about 2.5-3x its original density
thanks for the question; honestly, I had never wondered this before and, I replied somewhere else, now I really want to know. I think I got it, I am half way through the calculation; I promise a dedicated video to this in the near future.
@@Salien1999 I do not know the answer and when searching I found this "compression by a factor 2.5 to 3" but it was unclear whether this quoted range is for radius or volume. As promised above, I am working it out and I will post a dedicated video because I find it a very interesting question.
@@jkzero I'm looking forward to your results. In another YT video -- I can't remember which one -- there was a hint that the implosion caused the core actually to liquify! Wonder if that is possible. I guess as long as it was a roughly spherical blob for a few microseconds (nanoseconds?) it would go off anyway. And at this point you run into semantic questions such as what is a solid vs a liquid (metallic crystalline structure?). And it doesn't take long for the whole thing to turn into a plasma anyway. There's another subject to cover: how long this all takes. It's quite amazingly rapid. Far faster than even 1 frame of video.
I've read "grapefruit to lemon". Also, I've yet see anything showing how the "pit" was cast from the "urchin" getting encased in plutonium & all the other layers of stuff...this seems like a pretty tall order to figure that part out.
Very informative. Thank you..
Glad it was helpful!
@@jkzero an interesting video you might consider making: with a breakdown of the maths involved - similar to what's shown in this video - examine the rope trick effect.
The fact that _visible light_ was intense enough to vaporize the guy wires of various towers which housed nuclear test devices, is pretty remarkable..
@@SineEyed I cannot guarantee to be able to fulfill all the requests but I always open to collecting suggestions, thanks.
@@jkzero keep up the good work.. 👍
I think you're overlooking proximity. The light and heat was enough to raise clouds of rock vapor from the nearby sands.
Simple piece of analysis cuts through to the answer. 10 Suns. Gee, I love Physics. The bonus was the second bit, clarifying Oppenheimer's quote. Thank you.
Glad you enjoyed it! Make sure to check the other videos in the channel, plenty of nuclear-weapons physics and now quantum mechanics
🌎 = be kind to planets
There's a slight mistake there. The line "now I am become death" is not grammatically correct in English if 'become' is a verb. You would say "now I HAVE become death..." or "now I am becoming death...".
This confused me for years until I looked into it. The form that Vishnu takes is named "Become Death"; almost as if 'Become' is his first name and 'Death' is his last name. "Become Death" is a proper noun
So the correct quote would be: "Now I am 'Become Death', the destroyer of worlds..."
great that you point this out, as a non-native English speaker, the 'am' always confused me. I had to look it up because I thought the sentence was "Now I become death..." but the 'am' is there in all the transcripts of the interview, and once I read it I could not spot hearing it. I should point out that there are also discussions about this free translation done by Oppenheimer. In fact, for what I have read from people who can read the original scripture, the correct literal translation is not "Death" but "Time" so Vishnu claims to "become Time, the destroyer of worlds;" however, in the end Time here is understood as a metaphor for death, which would make Oppenheimer's translation somehow valid.
@@jkzero Amzing videos by the way! My PhD is in maths and whenever I try to explain things to people I get a glass-face...but you bring the maths to life--well done you!
thanks for the positive feedback; I am thrilled by the positive response to the videos, it has been great to find so many physics enthusiasts willing to get some math in addition to the stories
@@CaptainCalculusWhen was the last time a nuclear or atomic device was detonated?
@@ajarivas72 North Korea's underground test in 2017. The last time the US tested anything was in 1992
Sry but nukes don't exist enjoy the show Peter pan is next
Whoops. I spoke too soon. The first time I've actually watched a RUclips video that got to the point WAY before I did.
Anyway...
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FUN FACT!
What's consistently left out of the situation from the Bhagavad Gita, made famous after being widely misquoted by Oppenheimer, sounds to me like less of an existential Hindu threat and more like a temper tantrum thrown by a thoroughly pissed off Vishnu at some minor Hindu prince, who refused to scrub the toilets.
Here's the direct quote of Oppenheimer quoting Vishnu:
"Now I am become death, the destroyer of worlds!"
Am I the only one who notices the rotten grammar of a Hindu god being quoted here? Is it just me, or does Vishnu come off as a pissed off five year old, about to throw a tantrum?
Well, that's Vishnu, folks, a Hindu deity with the power to BECOME DEATH and DESTROY WORLDS, apparently.
Anyway, after several hours of failing to get the prince to do the dirty work in Hindu Heaven, Vishnu was completely fed up... so, taking on his multiarmed form, Vishnu threatens this prince with the famous quote that Oppenheimer took WAY out of context when he quoted it - you know, the part when Vishnu grew extra arms and threatened some unknown Hindu prince with death and destruction unless he got to work mopping the restrooms in heaven...
Oh! And in case anyone missed it, Vishnu threatened to destroy not just one world, but MULTIPLE WORLDS ! Assuming that includes planet Earth because Earth is the only world that, to the best of my knowledge still exactly fails to be plural must assume - with NOT EQUAL TO OR PRAYER THAN worlds - death and destruction! Because where are the other worlds? Oh it's referring to planet Earth? That's our world, folks. And I'm pretty sure it's the only one, for now. I hope Vishnu got the memo.
NOW TIME FOR A PRESSING QUESTION...
Why Vishnu thought he could threaten some anonymous Hindu prince with a threat to destroy WORLDS, still plural and still only planet Earth, would give a shit about our own planet, located in a remote section of the Milky Way known colloquially as the Orion spur, remains beyond me.
Regardless, we can get an idea of how effective this threat was at getting the prince to scrub the toilets by merely looking around...
FALSE ALARM!
After looking around, I'm pretty sure I can confidently say that we're all still here. That includes the entirety, including myself and you guys, of planet Earth.
Can someone confirm this, please? I need to get published in 'Nature' before I croak.
I am DEFINITELY NOT a Mathematician in ANY way, but tiyr CKEAR explanations are absolutely wonderful.
Thank yiy gir producing and Presenting your Videos!
I am glad you found the content of interest. Thanks for watching and welcome to the channel.
I know a lot about nuclear weapons from my time in the military and this was probably one of the best descriptions of the gadget shot that I have ever heard phenomenal summary of the process, I don't know about anyone else but I feel building excitement when I hear process of a fission bomb destinating.
If you think that was bright, fusion bombs produce enough light to temporarily blind someone who has their eyes closed and their hands in front of their eyes, and is facing away from the blast!