As an isotope geochemist, I find it hard to explain how surreal this all is - surreal to learn that nucleosynthesis happens quite differently than we all thought. Upheavals in scientific knowledge like this are rare. Our collective vision of a fundamental process has been fundamentally changed. Even better, the new story is far more amazing than the old one. Wow.
I also find it beautifully surreal to consider that scientists were able to trace back most of earths short-half-life materials to a single neutron star collision. We can get so caught up in our short lives on earth.. all the greedy politics and our imagined divisions.. I like to use realisations like this one, to put it all into perspective.. and see that we are just a blip, a footnote of a much larger cosmological story. All of humanity, everything we are so consumed by, could be wiped from existence by a minor cosmic event. Viewpoints like these make me wonder why everyone can't just chill the fuck out, and work towards something great
Sure, it's still the r-process. But that process is (primarily) happening somewhere else than we had thought. The supernova picture was so firmly ingrained into my imagination - and the imagination of many in the general public. Bringing neutron star collisions into that picture is not a small change. Also, the "bump" in platinum group element a abundance that we observe in our solar system suddenly makes a lot more sense. We can thank LIGO/VIRGO for that.
Hey Brian, I’m an aspiring geochemist as well. Currently studying geology at the City University of New York, I was wondering if it’s possible we could talk. Geologists around here are rare and it’s not often I find someone that has specialized in the same field I hope to be part of. I have a few questions about the industry, if it’s at all possible I’d love to hear back from you. All the best, Marc.
I've been around long enough to hear "we are star stuff", many times, and in many different forms and implications. Then I heard "we are supernova stuff", which was a little more. Then I heard "we are hypernova stuff" and, "we are colliding neutron star stuff" Well, I guess they're all still stars for the most stuff, but when it comes down to it, I think there is still more to the story. I predict we will soon be hearing "we are black hole stuff".
Really funny! But actually most atomic bombs (all of them really) use plutonium 239 (in combination with tritium) which is an artificially created element in nuclear reactors from uranium 238.
Now I feel the need for a T-shirt that says "contains 2ppm colliding neutron star material synthesized on the rim of a black hole before surfing a wave of neutrinos into the nebula that would eventually collapse into our solar system".
@@MrPopPopDrop yup. *_Yours!!!_* _just messing with ya. ya just left it out there. ...Ya know _*_someone's_*_ gonna hit ya up._ _(at least th kinda people I know....)_ ........✌
They can also give you free electricity as they bombard the earth's surface even as far as hundreds of meters below the earth's surface. I'm not going to list the metals required to complete the process however I will say that if two dows were created no matter there dimension with these elements which must be 30 in one and 32 in the other dow and place a light bulb on top of both dows it will illuminate until of course the life of the filament reaches its end 1452 hours whatever. So now you know another use. They may also mutate things to a small degree.
@ungratefulmetalpansy notice how they claim to have this knowledge but wont actually say how to do it, or do it themselves. Sounds like pretty much everybody that claims to have special knowledge to me.
@@Miranox2 Our only hope is to form a society of scribes to toil in obscurity for generation after generation. Brothers and Sisters of the Writing of the Big Number, hallowed be thy digits.
Oh man, this episode has blown my mind! It turns out that it is indeed incredibly rare to have a habitable planet formed with an abundance of heavy elements essential for life.
The LIGO gravitational waves discovery has turned into so much more - now neutron stars created the periodic table! Amazing year of exponential learning this episode was so worth waiting for!
This video made me so happy to be alive and have consciousness. We are the universe observing itself. What a beautiful idea. Thanks PBS Spacetime! Much love
I want to thank this show for massively leveling up my astronomy understanding! Thanx to your episodes, I have been lucky enough to be friend a top notch astronomy professor from UCSB! I’ve been given the most recent curriculum astronomy book and have a chance to sit in on some classes next quarter! Not bad for a guy who never really went to college😅
Hadn't thought about the cmd as infrared before. That's funny! Space wouldn't be the freezing vacuum it is today, it'd be quite warm for hundreds of millions of years. I wonder what that would've done to planet formation and weather patterns. The goldlocks zone would have to be much further from stars, but then you don't have the light from the star as a useful energy source anymore. Answer to the fermi paradox? Space had to cool down enough that starlight became useful on a higher proportion of planets. Pushes the time till sentient life can happen further forward. Add in maybe not enough heavy elements for a while and maybe that's part of the answer? Who knows.
Planets weren't forming until billions of years later. There was no iron or silicon or oxygen. Indeed it's possible that planet formation only became common in the second half of the universe's life, Earth could be quite an old world.
Now, given that the margin of error is about 6oo LY, I'm wondering if we can find any likely candidate BHs. Given how rare NS mergers are, I'm guessing that BH mergers are even rarer still.
Humanity: Screaming and rioting before falling silent as the earth slowly spirals into the event horizon. Meanwhile, on the atomic scale: Hey man, is that atom # 123,272,469,319,473,425? It's been _ages_ since I've seen you!
I like the fact that this channel not only recognizes memes, but also is truly part of meme culture. One of the things that made me subscribe to this channel are the funny remarks at the end, i swear to god the one where he calls someone while "stealing" someones comment as an idea for a book still gets me
"Today a young man on acid realized that all matter is merely energy condensed to a slow vibration, that we are all one consciousness experiencing itself subjectively, there is no such thing as death, life is only a dream, and we are the imagination of ourselves. Here's Tom with the Weather." -- Bill Hicks
The next time an old stick in the mud says how things were when they were young tell them that back then we didn't know that everything higher than 44 on the periodic table was made in neutron star collisions so viva la progress. I think of Louis Armstrong singing about children who would learn much more than he would ever know and how wonderful that makes the world. When I was born nothing had landed on Mars. When my father was born Hubble hadn't discovered the distance to Andromeda. The scientific march forward is one of the few things that gives me hope for the future.
"Today a young man on acid realized that all matter is merely energy condensed to a slow vibration, that we are all one consciousness experiencing itself subjectively, there is no such thing as death, life is only a dream, and we are the imagination of ourselves. Here's Tom with the Weather." -- Bill Hicks, another dead hero
Neutron Star alchemy could be a Great Filter of the Fermi Paradox - that low metallicity intelligent life would be condemned to an eternal stone age without the Bronze & Iron ages that we stumbled into on Earth.
If that includes iodine, then there would be no complex life on that planet, period. Does that make you guys happier to know that those aliens are in fact more likely to be microbes?
Luc Fauvarque if there's no one else in the Galaxy (yet) then it's a great opportunity for a "first!!111". But if there are lots of those pesky aliens then it's probably fine too.
This is what was going through my head the whole video until ~10:00 when he says neutron star collisions would occur approximately one per 20 million years. I was guessing they were a million times more common. If that rate was consistent, then there would only have been about 700 in the history of the galaxy... only 700 miniscule pinpoints in the galaxy for complex life to arise. Of course the rate of these collisions would have been higher, long ago, but how many would there be, really? 2000? 5000?
It's true, medians and averages are confoundingly not the same thing... at all! I'm always mixing them up and mathematically it can make a huge difference.
@@PeterB12345 not only in the mathematical sense, but also in a physical sense. Average lifetime and halflife are two different concepts in radioactive physics, having separate definitions.
I guess what he means, having a lot of heavy elements makes it easier to evolve on a technical level (technicaly advanced complex). Since we can assume that the universe might not be very homogenues, it is not far fetched to believe that it might have an influx on it... Edit: I'd like to add, that my thought came out of the fact, that the fermi-paradox is aimed at high-tech civs. Edit 2: And let us not forget, that a high (or low/non existant) background radiation due to heavy radioactive elements can and will have an impact on over biologic lifeform, esp. over billion of years of evolution. Edit 3: Changed "alot" to a lot since i forgot to press the spacebar.
There is both the effect on the development of complex life, and (perhaps even more importantly) the effect on the development of technology to consider.
So does it mean that we were very lucky to have a nearby neutron star collision to deliver us precious heavy elements in our solar system? If most of other star systems did not have that, I suppose it adds up to the Fermi paradox solution.
It's certainly part of the equation. Only certain pockets of stars would have been so seeded by heavier elements, and then you're counting on those elements to actually come together in appreciable amounts in a solar system of an appropriate configuration. Depending on how rare this seeding is, and how variable even the product of such seeding would be, it can significantly cut down the number of possible viable systems.
@@thevoicestoldmetoagain4627 They made a post on the community tab 2 weeks ago talking about their next video (I don't think it was meant to be this one).
@@theHusky2490 Yea but that short video doesnt really count for much if ya ask me. And i agree that this probably isnt the video related to that short clip they gave us.
So these atoms, formed from just outside the event horizon, billions of years ago, recombined to form me and can attempt to comprehend its creation? *DOPE*
There's no doubt a metric for determining which type of kersplosion is yuger - merger vs. nova. I'd tend to guess super novae are, but the neutron star merger is freakin' kewl.
I love your videos, but you guys really should get someone to look over the closed captions in your videos. R process becomes "our process" and such. It must be confusing to the deaf/hard of hearing. Hell, I'll do it.
Caption submissions are disabled for this video, so I guess I'll mention some corrections here. 1:38 "our process" should be "r-process" (this is repeated several times) 1:44 "that destroy missiles" should be "that this story misses" 3:20 "are protists" should be "r-process" 4:55 "group" should be "goop" 4:56 "destabilizers" should be "destabilizes" 6:33 "getting the mountains of the galaxy" should be "getting them out into the galaxy" 7:41 "they'll formed" should be "they were formed" 10:25 the URL-looking thing should be "that make up you" 10:34 "LEED Silver Gold" should be "lead, silver, gold" 11:54 most of the names got mangled 12:51 "reaiiy annive" should be "re-ionized" 13:00 "realization" should be "reionization" 13:02 "a tree nation" should be "at recombination" 13:05 "realization" should be "reionization"
@@jesseruderman5121 Additional corrections: 2:13: “low mass star” should be “lower mass stars” 2:20: “our protest” should be “r-process” 3:35: “cause of massive stars” should be “cores of massive stars” 3:39: “a density” should be “at densities” 5:12: “hopelessly unstable once” should be “hopelessly unstable ones” 5:15: “beat a decay” should be “beta decay” 5:23: “hour process” should be “r-process” 6:27: “neutral start collisions” should be “neutron star collisions”
Actually, it could be on the other side of the Milky Way by now. It was between 650 - 1300 ly at the moment of the accretion of our solar nebula. Since then, our solar system revolved at least 20 times around Sagittarius A* - i.e. the center of our galaxy. Due to different radial speeds, the resulting black hole and our Sun could have drifted apart tens of thousands of light years. Or it could be even a lot closer (12 ly), but without an accretion disk to feed on, it would be invisible for our detection efforts.
So glad you did this episode! Been waiting since the LIGO neutron star merger detection. Your explanations strike a great balance between technical detail and good narrative. Another great writer, Walt Whitman, had this to say 164 years ago: “I believe a leaf of grass is no less than the journey-work of the stars...”
Matt you're alive!!! Thank God for that, was beginning to worry.... Next time you take a couple of weeks out, could you post a little message saying you're ok? 🤓
13:14 Correct me if I'm wrong, but mean free path scales linearly, density scales cubically -> 100^3 lower density means 100 longer MFP, not million times longer.
@@quimicalobo61d It's super fun and hugely nostalgic for me, I'd suggest finding a nice server and making some friends or grabbing some buddies and giving it a try!
You must have changed cameras or the operator because this one looks way more sharp than usual. I don't want to come off as a bellend but on previous videos you can see the green screen stuff way sharper than Matt. Keep up the good work, you are the only physics channel that actually caters to physicist, instead of just laymen.
i am a total "layman" in therms of physics as I didn't study it and just am interested in it and satisfy that need by reading up a bit on it and watching some vids. However, I understand most of the things discussed in these videos. Is this what a real physics channel feels like?
@@hazardeur it goes in to topics that aren't as often explored and Matt isn't afraid to show us the mathematics. I think this is as close as a real physics channel, alonng with 3blue1brown,minutephyics,mathlogger,60 symbols and, others. Simply put they aren't using analogies but instead prefer to focus on the math. Kurtzergat is more towards layman who want a nice story with pictures.
@@wintervenom123 Ok makes sense, thank you! I actually do know (and love) Kurzgesagt but I can appreciate the more detailed channels like this here just as well
Hey, Matt! Here is the topic for some popularization of astronomy on Space Time channel. Nebulas: a lot of videos tells us the heavy material about the ways they are created (which is awesome), but not enough videos visualize it in a way, that they are so dim, that the person located in the center of it will not even see the difference. Nobody stresses it enough, that things we see in astronomy can't be seen by the human eye. With this realization, I have a lot of respect to an effort that's been put to enormous amount of data..
Could we incorporate the Neutron Star merger hypothesis into the Drake equation? That way we would "only" need to trace back every heavy metal enriched nebula to look for alien civilizations.
It puts an important constraint on time, along with supernovae explosions. The first stars couldn't have had planets and the following generation would have had few. 2/3 of the universe's life might have passed planetless. And different types of galaxies have different patterns of metal enrichment, as well as it varying within a galaxy. (The outer disk tends to have less, the core more but with sterilizing explosions every few millennia.)
You're assuming complex life can only happen when elements heavier than Iron are present. Considering anything past Calcium only amounts to 0.85% in our bodies (in mass, btw), I think that's a pretty wild guess right there
@@ajv336 Not sure that's the specific assumption, though. Sure, the assumption is based on our own history, but there are a number of elements that have been a part of our civilization since almost the beginning that are heavier than iron.
@@garethdean6382 Well, intuitively, I would think it would be less material generated simply because there's only 1 neutron star in that process instead of 2. I wonder about the efficiency of the process... I'd think that with a smaller black hole, the efficiency of elemental synthesis would increase because less of the material would be devoured.
It would depend. As far as I'm aware nobody's tried to model this, but a small black hole could indeed eject a lot of material as 'jets'. Of course bigger holes might be more common and they could swallow the neutron star more easily. As it is hardly any material escapes anyway.In a double merger maybe a few thousand Earth's worth out of a pair of stars multiple times heavier than our sun. That's not even an 0.1% survival rate.
@@garethdean6382 apparently it's called a kilonova... Don't know why Matt didn't tell us that -_- Anyway, there's gotta be a more efficient way to tear the things apart.
No, it could not. Heavy elements aren't directly necessary for Life. And also he never claimed we were lucky. These events are not rare on galactic timescales.
The presence of heavy elements seems important for the development of life by at least two different mechanisms: 1) Providing elements that can radioactively decay, maintaining a molten planetary core necessary to sustain a sufficiently strong magnetic field 2) Providing the large elements capable of being incorporated into enzymes to catalyse the essential biochemical reactions of life It seems like this neutron star collision is exceptionally near to the formation of the solar system, both in time and space. Leaning on the anthropic principle, might this mean that at least for the current generation of stars (Population I), proximity to a neutron star collision might be essential for life? If so. then the extreme rarity of neutron star collisions might also explain the extreme rarity of life.
does the r-process happen at all on supernovae ? because considering how rare neutron star collisions are, does that means that the abundance of rare elements on planets can vary drastically, to the point there are planets with no rare elements at all ? or are they common enough to spread rare elements uniformly through a galaxy even without the help of supernovae ?
Danilo Oliveira Thinking about the same thing. How frequent are these events? Frequent enough to have all these elements on most planets? Or are we a rare exception and most planets don’t have much heavier elements? In the later case, it is a nice addition to the Fermi-paradox.
@@juzoli I'd hazard a guess they happen frequently enough that over a long period of time (billions of years) you would end up with enough of that material being spread throughout a galaxy.
The estimated rate of neutron-star mergers is once every twenty million years in the Milky Way. There was a recent paper that argued that 80% of the r-process elements in the Universe come from an even rarer event: a collapsar supernova. While these events are rarer, they would transform a greater percentage of the total mass involved into r-process elements although there are physicists who dispute this hypothesis. Based on the cosmological principle, at the largest scales, these elements should be evenly distributed, but that does not mean that there can't be a great deal of local variation. While I can't speak for r-process elements, there have been a couple of studies involving elements necessary for life on Earth. One study of planetary nebula PNG 135.9+55.9 showed that it had an oxygen abundance less than 1/50 that of our solar system. There is another study I remember reading about phosphorus. It is the eleventh most common element on Earth, but it only makes up 0.0007% of all matter in the Universe. In comparing two nebulae, Cassiopeia A and the Crab Nebula, it was found that the ratio of phosphorus to iron in the former to be about 1 to 1.057 compared to about 1 to 12 in the latter; furthermore the ratio found in Cassiopeia A is about 100 times the average ration of the Milky Way as a whole. While these are not r-process elements, I would imagine the same scenario applies. Not every neighborhood is created elementally equally, and that may be a contributing factor to the Fermi Paradox. At the very least, if life exists elsewhere, the chances of it sharing a similar chemistry to ours are much lower.
@@curtisshaw1370 that is very interesting, I had no idea lighter elements could very like that. is Phosphorus created by nucleosynthesis ? I would imagine it to be very well distributed because of how many massive stars there were in the early universe.
Massive stars were abundant in the early universe, neutron stars collision were rather common. (and Galaxies werent that big) The amount of short-gamma flashes tells us how popular those collisions are. Now i wait for collision with white dwarf.
Speaking of Sagan I think he'd enjoy your prose; "You’re only a tenth of a gram of colliding neutron star material, but that means a part of you was synthesised on the edge of a black hole, riding a wave of neutrinos into the nebula that collapsed into our solar system. Those atoms would eventually find themselves sitting in a lifeform that could calculate the time and distance of their formation". Beautiful!
Well thank you very much! Finally the explanation that I've been waiting for ever since the news came out that Ligo / Virgo had measured the collision. I actually know one of the scientist of that measurement and the person was unable to explain me how exactly such a collision creates the heavier elements. I was indeed wondering if the process was by capturing neutrons or if perhaps the pure amount of energy that is released creates particles via E = mc2.
the moment you realize you're a massive amalgamation of cells that are amalgamations of molecules that are amalgamations of elements made in the cores of stars smashing into the cores of other dead stars
I was thinking along the same lines, is it possible that the heavier elements formed in a nutron pair merger seeding a solar system before said system star begins it's life, are part of the prerequisite for initial life to evolve such a amoeba.
But rare under what perspective? If you ask a galaxy if it expects to get it's next dose of neutron star merger in the next billion years, I think it'd likely answer "yes."
I am trying to understand if elements such as gold, uranium, etc are formed in such a chaotic process, how do they end up relatively concentrated in various parts of the earth?
Can you use the time and distance of the neutron star collision to find candidate black holes for being the remnant of our Solar System's heavy elements?
I was wondering this too, but I suspect that between how difficult non-feeding black holes are to see and the chaotic nature of galactic orbits over the time scales needed, it's probably not possible given current technology. Far-future telescopes gathering more high-resolution data paired with faster super-computers to process it all might be able to upgrade that to a "maybe" though.
@@QuantumLeaper25 I still think that black hole that was the "founder of our solar system" would be in our region of the galaxy. It might be hard to find, but just knowing it's out there is awesome
@@nmarbletoe8210 Our protostar might have moved through the neutron star explosion cloud in a different direction and with a different speed. I guess that black hole may have crossed the whole galaxy or even merged with the supermassive black hole.
Very likely yes. These elements are generally not essential to life. So them nbot being available shouldn't be a major showstopper. Having said that, there are some side effects (no magnetic field on the planet, lower radioactive environment (-> lower mutation rate)) that may still be negatively affected. But of course nobody knows for sure.
It's depressive to acknowledge that even with the most advanced futuristic alien-like tech, humans will never be able to approach the event horizon of a black hole, but it's jaw dropping to realize that 1/10 of a gram in each and one of us has already been there :O
In addition to the neutrino wind, I figure a lot of those newly formed atoms probably escaped via the new black hole's magnetic field, shooting out into space along the axes the same way quasars do. Also, I'm wearing more neutron star by-products on my ring finger than exist in my body? Still pretty cool.
As an isotope geochemist, I find it hard to explain how surreal this all is - surreal to learn that nucleosynthesis happens quite differently than we all thought.
Upheavals in scientific knowledge like this are rare. Our collective vision of a fundamental process has been fundamentally changed. Even better, the new story is far more amazing than the old one.
Wow.
I also find it beautifully surreal to consider that scientists were able to trace back most of earths short-half-life materials to a single neutron star collision. We can get so caught up in our short lives on earth.. all the greedy politics and our imagined divisions.. I like to use realisations like this one, to put it all into perspective.. and see that we are just a blip, a footnote of a much larger cosmological story. All of humanity, everything we are so consumed by, could be wiped from existence by a minor cosmic event.
Viewpoints like these make me wonder why everyone can't just chill the fuck out, and work towards something great
Sure, it's still the r-process. But that process is (primarily) happening somewhere else than we had thought.
The supernova picture was so firmly ingrained into my imagination - and the imagination of many in the general public. Bringing neutron star collisions into that picture is not a small change.
Also, the "bump" in platinum group element a abundance that we observe in our solar system suddenly makes a lot more sense. We can thank LIGO/VIRGO for that.
@@brianharms1751 May be -- this is still a book being written and is mostly based on extremely elaborate and remote observation and inference.
Hey Brian, I’m an aspiring geochemist as well. Currently studying geology at the City University of New York, I was wondering if it’s possible we could talk. Geologists around here are rare and it’s not often I find someone that has specialized in the same field I hope to be part of. I have a few questions about the industry, if it’s at all possible I’d love to hear back from you. All the best, Marc.
I've been around long enough to hear "we are star stuff", many times, and in many different forms and implications. Then I heard "we are supernova stuff", which was a little more. Then I heard "we are hypernova stuff" and, "we are colliding neutron star stuff" Well, I guess they're all still stars for the most stuff, but when it comes down to it, I think there is still more to the story. I predict we will soon be hearing "we are black hole stuff".
Imagine being an uranium atom inside a nuclear bomb.
"I didn't escape a black hole for _THIS_ "
Ok that was really funny!
you can be a very good memer🤣🤣🤣🤣🤣🤣🤣
@@Tech2Galaxy Is this an official profession?
Really funny! But actually most atomic bombs (all of them really) use plutonium 239 (in combination with tritium) which is an artificially created element in nuclear reactors from uranium 238.
Why can't we all just get along?
Now I feel the need for a T-shirt that says "contains 2ppm colliding neutron star material synthesized on the rim of a black hole before surfing a wave of neutrinos into the nebula that would eventually collapse into our solar system".
He should wear a MAGA T-shirt
^ You ever see a comment so dumb it makes you question the intelligence of humanity?
@@MrPopPopDrop yup. *_Yours!!!_*
_just messing with ya. ya just left it out there. ...Ya know _*_someone's_*_ gonna hit ya up._
_(at least th kinda people I know....)_
........✌
Thats a great idea!
The shirt would be clever, if a bit "wordy."
I'd buy it, but not if you charge by the _letter!_
Neutrinos finally doing something really useful!
They can also give you free electricity as they bombard the earth's surface even as far as hundreds of meters below the earth's surface. I'm not going to list the metals required to complete the process however I will say that if two dows were created no matter there dimension with these elements which must be 30 in one and 32 in the other dow and place a light bulb on top of both dows it will illuminate until of course the life of the filament reaches its end 1452 hours whatever. So now you know another use. They may also mutate things to a small degree.
@ungratefulmetalpansy notice how they claim to have this knowledge but wont actually say how to do it, or do it themselves. Sounds like pretty much everybody that claims to have special knowledge to me.
@@Sciguy95 People just want to feel special. They prefer comforting lies to uncomfortable truths.
neutrinos for prez
Yeah, but I can't guess why that would be,
they radiate into all directions equally.
14:26 One hydrogen atom per square metre? I didn't know you're a flat spacetimer, Matt!
Is he talking about the two dimensional surface that projects our three dimensional holographic universe?
@@MrGonzonator He would probably explicitly mention it
Well universe is actually flat.
@@deater4989 Not that flat ;)
Stop fat-shaming black holes! Real space time has curves!
Didn’t expect a science exploration video to throw out straight facts for 10 min, then end with “rip Grumpy”
Watch enough of the channel and that actually starts to feel typical.
but that is lovely
@Enter the Bragn’ it really is
"Quantom mechanics forbids that!" is definitely your "You shall not pass!".
Some german cat would argue...
> Quantom mechanics
Quantom & Jerry?
12:14 My comment got mentioned. My life is now complete.
Replying to this in hopes you come back and are reminded of this :)
Why yes I would like to take time out of my completely non-cosmology related work day to learn more space.
*Hood Glasses*
I went to the bathroom in order to watch this on 2x speed as to not be too suspicious lol
@@Kyle_Schaff
Good thing you weren't caught. You would have had a lot of awkward explaining to do! 😀
This is astrophysics. Cosmology is much grander, it’s the study of the universe.
^Get this man his own show!
Literally me.
Finally, the explanation of how neutron stars create these elements I was waiting for. Fantastic job PBS Spacetime!
I'm finally relaxed after injecting to my brain my dosis of PBS Space Time
I've been calm ever since Nick Lucid said "EVERYBODY CALM DOWN!"
Heroin for me
I've noticed my cat loves the sound of your voice. She always moves closer when she hears you.
Is that Schrodinger's cat?
Me too though.
Is that code?
Gay?
I think the cat might be attracted partly also to your own calm and relaxed absorption in it.
"...wind of neutrinos is so intense..."
This is the official point when energies involved can be called "silly".
How much denser was the neutrino flow to do that??? Wild.
anything larger than ten to the wow is silly magnitude
@@nmarbletoe8210 How do you write "ten to the wow"?
@@Miranox2 Our only hope is to form a society of scribes to toil in obscurity for generation after generation. Brothers and Sisters of the Writing of the Big Number, hallowed be thy digits.
@@nmarbletoe8210 How about just 10^wow
A complex series of processes explained fully enough to induce headaches. One of the best...
Oh man, this episode has blown my mind! It turns out that it is indeed incredibly rare to have a habitable planet formed with an abundance of heavy elements essential for life.
I love the fact that you have so much intelligence, knowledge
and enthusiasm for such a deep and complex subject, Matt!
The LIGO gravitational waves discovery has turned into so much more - now neutron stars created the periodic table! Amazing year of exponential learning this episode was so worth waiting for!
The graphics department really spared no expense in this one! Great job!
One of the best videos PBSST has ever done!
I MISSED YOU GUYS! PLEASE DON'T LEAVE US FOR SO LONG 😥
Now I can calmly watch the video. Today's a good day.
This video made me so happy to be alive and have consciousness. We are the universe observing itself. What a beautiful idea. Thanks PBS Spacetime! Much love
I want to thank this show for massively leveling up my astronomy understanding!
Thanx to your episodes, I have been lucky enough to be friend a top notch astronomy professor from UCSB! I’ve been given the most recent curriculum astronomy book and have a chance to sit in on some classes next quarter! Not bad for a guy who never really went to college😅
I never would've thought I'd hear Matt say "Rest in peace Harambe"
Dicks out!
AJ V Wayy ahead of you.
It's funny how of all people, it's the guy with a _V_ in his screenname who talks about the _D_
Hadn't thought about the cmd as infrared before. That's funny! Space wouldn't be the freezing vacuum it is today, it'd be quite warm for hundreds of millions of years. I wonder what that would've done to planet formation and weather patterns. The goldlocks zone would have to be much further from stars, but then you don't have the light from the star as a useful energy source anymore. Answer to the fermi paradox? Space had to cool down enough that starlight became useful on a higher proportion of planets. Pushes the time till sentient life can happen further forward. Add in maybe not enough heavy elements for a while and maybe that's part of the answer? Who knows.
Planets weren't forming until billions of years later. There was no iron or silicon or oxygen. Indeed it's possible that planet formation only became common in the second half of the universe's life, Earth could be quite an old world.
This is hands down one of the most profound and inspirational videos on all of TH-cam. @11:07 just blows my mind every time.
So somewhere out there is the black hole that formed the same time our heavy atoms did.
That's wild.
Now, given that the margin of error is about 6oo LY, I'm wondering if we can find any likely candidate BHs. Given how rare NS mergers are, I'm guessing that BH mergers are even rarer still.
We should really try to find the Founder bh! It's probably around here somewhere
Imagine if it wanders too close and Eats the Earth -- That's how my days go some times
@@mikesawyer1336 In that case I guess we'd be going home.
Humanity: Screaming and rioting before falling silent as the earth slowly spirals into the event horizon.
Meanwhile, on the atomic scale: Hey man, is that atom # 123,272,469,319,473,425? It's been _ages_ since I've seen you!
I like the fact that this channel not only recognizes memes, but also is truly part of meme culture. One of the things that made me subscribe to this channel are the funny remarks at the end, i swear to god the one where he calls someone while "stealing" someones comment as an idea for a book still gets me
You guys really upped the motion game lately. Nice stuff!
We are the universe observing and experiencing itself.
"Today a young man on acid realized that all matter is merely energy condensed to a slow vibration, that we are all one consciousness experiencing itself subjectively, there is no such thing as death, life is only a dream, and we are the imagination of ourselves. Here's Tom with the Weather." -- Bill Hicks
@XY ZW I like how your channel's playlists are all about complete nonsense quackery, delicious irony.
@@LaGuerre19 that's cool!
Sara Anne Miller how original
We are the universe trying to understand itself.
The next time an old stick in the mud says how things were when they were young tell them that back then we didn't know that everything higher than 44 on the periodic table was made in neutron star collisions so viva la progress.
I think of Louis Armstrong singing about children who would learn much more than he would ever know and how wonderful that makes the world. When I was born nothing had landed on Mars. When my father was born Hubble hadn't discovered the distance to Andromeda. The scientific march forward is one of the few things that gives me hope for the future.
"Today a young man on acid realized that all matter is merely energy condensed to a slow vibration, that we are all one consciousness experiencing itself subjectively, there is no such thing as death, life is only a dream, and we are the imagination of ourselves. Here's Tom with the Weather." -- Bill Hicks, another dead hero
“Tool riffs in the background”
"another dead hero"
I read it just after Norm MacDonald died, oof
@@TransRoofKorean Or so the Germans would have us believe.
This is hands down one of the most profound and inspirational videos on all of TH-cam. @11:07 just blows my mind every time.
Best PBS Space Time vid so far (up to the point where Matt changes shirts). I love prequel stories about alchemy.
Grumpy Cat was/wasn't grumpy. Owners said "Sweet, purring all the time."
This video is pure gold!
*ba dum tss!* 🥁 😂 🤣 😅
Neutron Star alchemy could be a Great Filter of the Fermi Paradox - that low metallicity intelligent life would be condemned to an eternal stone age without the Bronze & Iron ages that we stumbled into on Earth.
If that includes iodine, then there would be no complex life on that planet, period. Does that make you guys happier to know that those aliens are in fact more likely to be microbes?
Luc Fauvarque if there's no one else in the Galaxy (yet) then it's a great opportunity for a "first!!111". But if there are lots of those pesky aliens then it's probably fine too.
Hemoglobin's going to be a little weak..
@@lucofparis4819 It does include Iodine. Anything heavier than iron, apparently, and Iodine is twice as heavy.
This is what was going through my head the whole video until ~10:00 when he says neutron star collisions would occur approximately one per 20 million years. I was guessing they were a million times more common.
If that rate was consistent, then there would only have been about 700 in the history of the galaxy... only 700 miniscule pinpoints in the galaxy for complex life to arise. Of course the rate of these collisions would have been higher, long ago, but how many would there be, really? 2000? 5000?
One tiny correction. Half-lifes are not average decay times. They are median (50 percentile) decay times. Average decay time is ~half-life/ln(2)
Median is a type of average. You are describing the mean decay time, which is also a type of average.
@@Kowzorz Not in the mathematical sense. It's very different. In this case the two concepts vary by around 45%. But I did say tiny.
It's true, medians and averages are confoundingly not the same thing... at all! I'm always mixing them up and mathematically it can make a huge difference.
@@PeterB12345 not only in the mathematical sense, but also in a physical sense. Average lifetime and halflife are two different concepts in radioactive physics, having separate definitions.
@@aayusharya6899 I don't doubt that, math is the language of physics after all
"collapsed grumpy's wave function to can't haz cheeseburger just by talking about it" hahaha
Benjamin Shurts my sentiments exactly. I swear I said the exact words to myself. He just HAD to observe him didn’t he?
could the rarity of neutron star mergers be a Fermi Paradox explanation? Complex life cannot exist without heavy elements.
I guess what he means, having a lot of heavy elements makes it easier to evolve on a technical level (technicaly advanced complex). Since we can assume that the universe might not be very homogenues, it is not far fetched to believe that it might have an influx on it...
Edit: I'd like to add, that my thought came out of the fact, that the fermi-paradox is aimed at high-tech civs.
Edit 2: And let us not forget, that a high (or low/non existant) background radiation due to heavy radioactive elements can and will have an impact on over biologic lifeform, esp. over billion of years of evolution.
Edit 3: Changed "alot" to a lot since i forgot to press the spacebar.
To my knowledge, observations in the past 5 years have shown us that these kilonova are more common than we thought.
There is both the effect on the development of complex life, and (perhaps even more importantly) the effect on the development of technology to consider.
@@Hartschteiler a lot*
@James Flames Could be. Could also be not essential but merely facilitating. Doesn't look like it from what I know, but then again I don't know much.
So does it mean that we were very lucky to have a nearby neutron star collision to deliver us precious heavy elements in our solar system? If most of other star systems did not have that, I suppose it adds up to the Fermi paradox solution.
It's certainly part of the equation. Only certain pockets of stars would have been so seeded by heavier elements, and then you're counting on those elements to actually come together in appreciable amounts in a solar system of an appropriate configuration.
Depending on how rare this seeding is, and how variable even the product of such seeding would be, it can significantly cut down the number of possible viable systems.
PBS Spacetime: *makes post after 2 weeks of silence*
Me: STOP EVERYTHING!
3 weeks of silence
@@thevoicestoldmetoagain4627 They made a post on the community tab 2 weeks ago talking about their next video (I don't think it was meant to be this one).
@@theHusky2490 Yea but that short video doesnt really count for much if ya ask me.
And i agree that this probably isnt the video related to that short clip they gave us.
Wonderful explanation and animation
So these atoms, formed from just outside the event horizon, billions of years ago, recombined to form me and can attempt to comprehend its creation?
*DOPE*
Amazing, arguably a more violent process than originally thought.
There's no doubt a metric for determining which type of kersplosion is yuger - merger vs. nova. I'd tend to guess super novae are, but the neutron star merger is freakin' kewl.
I love your videos, but you guys really should get someone to look over the closed captions in your videos.
R process becomes "our process" and such. It must be confusing to the deaf/hard of hearing. Hell, I'll do it.
Caption submissions are disabled for this video, so I guess I'll mention some corrections here.
1:38 "our process" should be "r-process" (this is repeated several times)
1:44 "that destroy missiles" should be "that this story misses"
3:20 "are protists" should be "r-process"
4:55 "group" should be "goop"
4:56 "destabilizers" should be "destabilizes"
6:33 "getting the mountains of the galaxy" should be "getting them out into the galaxy"
7:41 "they'll formed" should be "they were formed"
10:25 the URL-looking thing should be "that make up you"
10:34 "LEED Silver Gold" should be "lead, silver, gold"
11:54 most of the names got mangled
12:51 "reaiiy annive" should be "re-ionized"
13:00 "realization" should be "reionization"
13:02 "a tree nation" should be "at recombination"
13:05 "realization" should be "reionization"
@@jesseruderman5121 Additional corrections:
2:13: “low mass star” should be “lower mass stars”
2:20: “our protest” should be “r-process”
3:35: “cause of massive stars” should be “cores of massive stars”
3:39: “a density” should be “at densities”
5:12: “hopelessly unstable once” should be “hopelessly unstable ones”
5:15: “beat a decay” should be “beta decay”
5:23: “hour process” should be “r-process”
6:27: “neutral start collisions” should be “neutron star collisions”
One of your best episodes yet Dr Matt!!
It's fascinating to think that the black hole remnant of that merger is still out there, relatively nearby, waiting to be discovered.
Our sibling black hole.
Actually, it could be on the other side of the Milky Way by now. It was between 650 - 1300 ly at the moment of the accretion of our solar nebula. Since then, our solar system revolved at least 20 times around Sagittarius A* - i.e. the center of our galaxy. Due to different radial speeds, the resulting black hole and our Sun could have drifted apart tens of thousands of light years. Or it could be even a lot closer (12 ly), but without an accretion disk to feed on, it would be invisible for our detection efforts.
5:30 how heavy can the elements get?
3:11 how large of neutron stars will collapse together?
I wonder how many byproducts reach the fabled "island of stability" where atoms have like 126 protons.
Dude, where have you been? Feels like epochs passed.
Spacetime passed! 😉
Feels like Eons* passed :^)
@@PhilerinoBTW considering we live in a simulation... Epochs passed :P
So glad you did this episode! Been waiting since the LIGO neutron star merger detection. Your explanations strike a great balance between technical detail and good narrative. Another great writer, Walt Whitman, had this to say 164 years ago: “I believe a leaf of grass is no less than the journey-work of the stars...”
Matt you're alive!!!
Thank God for that, was beginning to worry....
Next time you take a couple of weeks out, could you post a little message saying you're ok? 🤓
Manages to effectively explain complex ideas and equations while keeping up to date with modern memes. Truly the work of a genius.
"when i was in astrophysist school" omg what a flex 😍
13:14 Correct me if I'm wrong, but mean free path scales linearly, density scales cubically -> 100^3 lower density means 100 longer MFP, not million times longer.
Big fan though
Thanks for the beautiful visuals!
It's a source of constant amazement to me how much we can figure out.
*"the periodic table of Minecraft"*
dude I need that shirt lmao
Had it as a poster on my wall!
I never played this game but I found this shirt very interesting! Sometimes I have the curiosity to play it.. :)
@@quimicalobo61d It's super fun and hugely nostalgic for me, I'd suggest finding a nice server and making some friends or grabbing some buddies and giving it a try!
You must have changed cameras or the operator because this one looks way more sharp than usual. I don't want to come off as a bellend but on previous videos you can see the green screen stuff way sharper than Matt. Keep up the good work, you are the only physics channel that actually caters to physicist, instead of just laymen.
i am a total "layman" in therms of physics as I didn't study it and just am interested in it and satisfy that need by reading up a bit on it and watching some vids. However, I understand most of the things discussed in these videos. Is this what a real physics channel feels like?
@@hazardeur it goes in to topics that aren't as often explored and Matt isn't afraid to show us the mathematics. I think this is as close as a real physics channel, alonng with 3blue1brown,minutephyics,mathlogger,60 symbols and, others. Simply put they aren't using analogies but instead prefer to focus on the math. Kurtzergat is more towards layman who want a nice story with pictures.
@@wintervenom123 Ok makes sense, thank you! I actually do know (and love) Kurzgesagt but I can appreciate the more detailed channels like this here just as well
I love it that I just don’t quite understand what you’re teaching. But I’ll keep listening 🙂
Atanarjuat what didn’t you understand?
I’m a little slow, in a way, and I almost need to stop and think about every sentence he says. Only then can I fully understand what he’s saying.
TH-cam's felt kinda stale for me lately so I was super hyped to see a new Space Time. It's a good day!
Actually, Carl Sagan said: "We are the stuff of stars". Not that it makes much of a difference, but I remember the words from his mouth to my ears.
the medallion effect strikes again
Hey, Matt!
Here is the topic for some popularization of astronomy on Space Time channel.
Nebulas: a lot of videos tells us the heavy material about the ways they are created (which is awesome), but not enough videos visualize it in a way, that they are so dim, that the person located in the center of it will not even see the difference.
Nobody stresses it enough, that things we see in astronomy can't be seen by the human eye.
With this realization, I have a lot of respect to an effort that's been put to enormous amount of data..
Could we incorporate the Neutron Star merger hypothesis into the Drake equation? That way we would "only" need to trace back every heavy metal enriched nebula to look for alien civilizations.
Given NS merger rarity, that would be an important variable.
It puts an important constraint on time, along with supernovae explosions. The first stars couldn't have had planets and the following generation would have had few. 2/3 of the universe's life might have passed planetless. And different types of galaxies have different patterns of metal enrichment, as well as it varying within a galaxy. (The outer disk tends to have less, the core more but with sterilizing explosions every few millennia.)
You're assuming complex life can only happen when elements heavier than Iron are present. Considering anything past Calcium only amounts to 0.85% in our bodies (in mass, btw), I think that's a pretty wild guess right there
@@ajv336 Not sure that's the specific assumption, though. Sure, the assumption is based on our own history, but there are a number of elements that have been a part of our civilization since almost the beginning that are heavier than iron.
@@ajv336 The drake equation doesn't estimate the number of living planets, but planets with currently active radio-based technology.
One of the best episodes of this show ever
Holy $h!7 this lead-out-to-"spacetime" was like a monster combo. We could see you really getting into it, Matt.
For such an interesting subject matter, nothing puts me to sleep more than space time. I can't help it. I fall comatose instantly
Love the animations
This knowledge can add perspective to folks trying to prioritize problems that are, in fact, trivial yet seem monumental
They way you described the element creation process, it sounds like it would also work with neutron star-black hole collisions too.
It should, as the neutron star is fragmented in the same way.There'd be much less though since the star won't collide with the hole and 'splatter'.
@@garethdean6382 Well, intuitively, I would think it would be less material generated simply because there's only 1 neutron star in that process instead of 2. I wonder about the efficiency of the process... I'd think that with a smaller black hole, the efficiency of elemental synthesis would increase because less of the material would be devoured.
It would depend. As far as I'm aware nobody's tried to model this, but a small black hole could indeed eject a lot of material as 'jets'. Of course bigger holes might be more common and they could swallow the neutron star more easily. As it is hardly any material escapes anyway.In a double merger maybe a few thousand Earth's worth out of a pair of stars multiple times heavier than our sun. That's not even an 0.1% survival rate.
@@garethdean6382 apparently it's called a kilonova... Don't know why Matt didn't tell us that -_-
Anyway, there's gotta be a more efficient way to tear the things apart.
The best music to match this video
So apparently, we were incredibly lucky to have so much of those heavy elements?
I wonder, could this be a great filter?
No, it could not. Heavy elements aren't directly necessary for Life. And also he never claimed we were lucky. These events are not rare on galactic timescales.
@@ObjectsInMotion They may not be directly necessary for life, but maybe they are directly necessary for intelligent, organized life?
@Connor N - How do you define intelligence?
@@khatharrmalkavian3306 only in terms of the drake equation
@@khatharrmalkavian3306 a civilization that is just as or more advanced then our own.
This is one of the most interesting new things I have learned this year.
so, I'm about 10-4 % neutron star!
AWESOME!!!!
This is the best TH-cam channel in spacetime.
The presence of heavy elements seems important for the development of life by at least two different mechanisms:
1) Providing elements that can radioactively decay, maintaining a molten planetary core necessary to sustain a sufficiently strong magnetic field
2) Providing the large elements capable of being incorporated into enzymes to catalyse the essential biochemical reactions of life
It seems like this neutron star collision is exceptionally near to the formation of the solar system, both in time and space. Leaning on the anthropic principle, might this mean that at least for the current generation of stars (Population I), proximity to a neutron star collision might be essential for life? If so. then the extreme rarity of neutron star collisions might also explain the extreme rarity of life.
My favourite Neutron is Jimmy, he's one hell of a star.
The pizza is aggressive.
does the r-process happen at all on supernovae ? because considering how rare neutron star collisions are, does that means that the abundance of rare elements on planets can vary drastically, to the point there are planets with no rare elements at all ? or are they common enough to spread rare elements uniformly through a galaxy even without the help of supernovae ?
Danilo Oliveira Thinking about the same thing. How frequent are these events? Frequent enough to have all these elements on most planets? Or are we a rare exception and most planets don’t have much heavier elements?
In the later case, it is a nice addition to the Fermi-paradox.
@@juzoli I'd hazard a guess they happen frequently enough that over a long period of time (billions of years) you would end up with enough of that material being spread throughout a galaxy.
The estimated rate of neutron-star mergers is once every twenty million years in the Milky Way. There was a recent paper that argued that 80% of the r-process elements in the Universe come from an even rarer event: a collapsar supernova. While these events are rarer, they would transform a greater percentage of the total mass involved into r-process elements although there are physicists who dispute this hypothesis. Based on the cosmological principle, at the largest scales, these elements should be evenly distributed, but that does not mean that there can't be a great deal of local variation. While I can't speak for r-process elements, there have been a couple of studies involving elements necessary for life on Earth. One study of planetary nebula PNG 135.9+55.9 showed that it had an oxygen abundance less than 1/50 that of our solar system. There is another study I remember reading about phosphorus. It is the eleventh most common element on Earth, but it only makes up 0.0007% of all matter in the Universe. In comparing two nebulae, Cassiopeia A and the Crab Nebula, it was found that the ratio of phosphorus to iron in the former to be about 1 to 1.057 compared to about 1 to 12 in the latter; furthermore the ratio found in Cassiopeia A is about 100 times the average ration of the Milky Way as a whole. While these are not r-process elements, I would imagine the same scenario applies. Not every neighborhood is created elementally equally, and that may be a contributing factor to the Fermi Paradox. At the very least, if life exists elsewhere, the chances of it sharing a similar chemistry to ours are much lower.
@@curtisshaw1370 that is very interesting, I had no idea lighter elements could very like that. is Phosphorus created by nucleosynthesis ? I would imagine it to be very well distributed because of how many massive stars there were in the early universe.
Massive stars were abundant in the early universe, neutron stars collision were rather common. (and Galaxies werent that big)
The amount of short-gamma flashes tells us how popular those collisions are. Now i wait for collision with white dwarf.
Speaking of Sagan I think he'd enjoy your prose; "You’re only a tenth of a gram of colliding neutron star material, but that means a part of you was synthesised on the edge of a black hole, riding a wave of neutrinos into the nebula that collapsed into our solar system. Those atoms would eventually find themselves sitting in a lifeform that could calculate the time and distance of their formation".
Beautiful!
The graphics helped a lot to understand you.
Neutron stars are my favorite visualization to walk on.
Well thank you very much! Finally the explanation that I've been waiting for ever since the news came out that Ligo / Virgo had measured the collision. I actually know one of the scientist of that measurement and the person was unable to explain me how exactly such a collision creates the heavier elements. I was indeed wondering if the process was by capturing neutrons or if perhaps the pure amount of energy that is released creates particles via E = mc2.
I have to say, being partly made of matter synthesized on the rim of a black hole, that escaped on a wave of neutrinos, feels pretty good.
Ok, you gave me a great pick up line. "When I was in astro physicist school...".
the moment you realize you're a massive amalgamation of cells that are amalgamations of molecules that are amalgamations of elements made in the cores of stars smashing into the cores of other dead stars
I really missed you last week. But you made up for it for acknowledging the memes at the end!
Finally, an episode that I can understand more than half of it!
This probably helps explain the fermi paradox, if a life forming planet relies on being seeded by a rare collision.
I was thinking along the same lines, is it possible that the heavier elements formed in a nutron pair merger seeding a solar system before said system star begins it's life, are part of the prerequisite for initial life to evolve such a amoeba.
But rare under what perspective? If you ask a galaxy if it expects to get it's next dose of neutron star merger in the next billion years, I think it'd likely answer "yes."
@@kindlin you poor fool. if you asked the galaxy that, the galaxy would make you sleep on the couch for a week.
I am trying to understand if elements such as gold, uranium, etc are formed in such a chaotic process, how do they end up relatively concentrated in various parts of the earth?
Can you use the time and distance of the neutron star collision to find candidate black holes for being the remnant of our Solar System's heavy elements?
I was wondering this too, but I suspect that between how difficult non-feeding black holes are to see and the chaotic nature of galactic orbits over the time scales needed, it's probably not possible given current technology. Far-future telescopes gathering more high-resolution data paired with faster super-computers to process it all might be able to upgrade that to a "maybe" though.
That makes sense... but I couldn't help but ask...
@@QuantumLeaper25 I still think that black hole that was the "founder of our solar system" would be in our region of the galaxy. It might be hard to find, but just knowing it's out there is awesome
@@nmarbletoe8210 Our protostar might have moved through the neutron star explosion cloud in a different direction and with a different speed. I guess that black hole may have crossed the whole galaxy or even merged with the supermassive black hole.
How does studying space not make you go insane. The part about the meteorite alone is just !!!!!!!!!
It's called REcombination because it was all combined before in the singularity to begin with.
The audio quality is sounding great! Thanks for continuing to work on improvements!
green screen removal on the other hand.. His face looks desaturated..
Productivity can wait. This is more important.
So, without that heavy element contribution from Neutron star collisions, would life even be possible?
Very likely yes. These elements are generally not essential to life. So them nbot being available shouldn't be a major showstopper. Having said that, there are some side effects (no magnetic field on the planet, lower radioactive environment (-> lower mutation rate)) that may still be negatively affected. But of course nobody knows for sure.
That was a fast click!
Fast fast!
I especially loved this episode. Answered so many questions!
exactly
Can we have a journal club episode of the "predicting" quantum jumps
It's depressive to acknowledge that even with the most advanced futuristic alien-like tech, humans will never be able to approach the event horizon of a black hole, but it's jaw dropping to realize that 1/10 of a gram in each and one of us has already been there :O
In addition to the neutrino wind, I figure a lot of those newly formed atoms probably escaped via the new black hole's magnetic field, shooting out into space along the axes the same way quasars do.
Also, I'm wearing more neutron star by-products on my ring finger than exist in my body? Still pretty cool.
You sure? Phosphates make up the finger upon which your ring sits.. :)
What a brilliant video.
I am a biologist. Not a physicist but I still like this video so much
Physics and stamp collecting. :-)
When in the universes history would neutron stars collide for the first time? 🤔 these elements are probably necessary for complex life
I’ve watched this episode a lot never gets old!