This table was also featured at Astronomy Picture Of the Day website (APOD for short) few days ago [1]. Judging by the tags in the tweet, author took it from there.
The wikipedia entry is substantially different. The twitter version only labels 6 of 7 categories and what would appear to be multiple elements miscategorized.
For some completely irrational reason I was slightly disappointed that the gold in my wedding ring was only from a neutron star merger and probably not from a supernova.
However, reading the relevant wikipedia page I came across this part:
"this single neutron star merger event generated between 3 and 13 Earth masses of gold"
While the neutron-star merger suggested that a substantial fraction of the r-process occurs in neutron stars, it does not rule out the possibility that the r-process also occurs in supernovae (the other leading candidate).
I'd be happy to wager that at least a couple percent of your wedding ring's nuclei were formed in a supernova.
Two neutron stars merging is an extremely energetic event which emits vast amounts of degenerate neutron star material at speeds above escape velocity. Pretty much instantly after this material is liberated from the pressure and gravity of the neutron star, it starts decaying into normal matter, producing a vast menagerie of (generally very neutron-rich) elements, which then follow their decay chains until they end up as mostly stable elements.
Low-mass stars, like the Sun, will generally expand into many times their original size after hydrogen starts running out in their core. Much of these tenuous outer layers will be emitted during the final stages of the star, before the core collapses into a white dwarf.
I've always wondered, does the presence of heavy elements on earth (ones which are likely to have formed via neutron star mergers) indicate that a pair of neutron stars merged relatively nearby our sun when it formed? Or is there just a diffuse amount of these elements in typical protostellar clouds all over the galaxy?
Perhaps a simpler way of asking: are the heavy elements we find on earth typical for an average planet? Or does a planetary system have to be "lucky" enough to have formed near a neutron star merger, for it to have elements like gold in measurable quantities?
The collision is messy and it splatters a huge amount of neutronium into space. This dissociates into a very hot mist of heavy elements, which eventually mixes into the surrounding nebula. The proto-solar disk was formed from this mixture.
Our sun is about 4.6B year old. There were a few other generations of stars that lived and died before our sun came about, and these spewed out the heavier elements that make up our solar system.
The ratio of heavier elements to H & He is called metallicity, and it is a measurable characteristic of stars, which are classed into Type I (high metallicity) and Type II (low) populations. Low-metallicity Type II stars are generally older.
Nothing specific on what Type II stellar systems and planets would be like, though I'd suspect gas giants, generally.
The follow up question is, how come the different elements aren't uniformly mixed within the earth. Or perhaps formed into stratified layers with the densest at the centre? E.g. Why are there 'deposits' of gold relatively close to the surface? Something to do with interaction of the physical and chemical properties of the elements with local variations in conditions?
The Earth is mostly stratified: light rocky silicate crust, heavier (though also rocky) magnesium-silicate mantle, core of mostly nickle-iron and heavier elements, which formed during the iron catastrophe.
Crustal deposits of heavier minerals largely result from late bombardment (after the crust had formed, about 100 million years after Earth's formation itself), geothermal and tectonic activity (volcanism, rift zones, vents), and biological mobilisation and concentration (e.g., lighter elements in coal and limestone, but notably, banded iron formations). Events such as the hypothesized Tethys collision could of course also have influenced distribution.
Gold forms veins typically in quartzes through differential precipitation AFAIU.
Ore formation is its own fascinating subfield of geology, and is underappreciated by many advocates of space mining.
All Earth's primordial gold sank. So, all the gold we find or mine came from meteorites (including dust) after solidification. Most has been dissolved in water.
Those who would like to know more could do worse than pick up Greenwood's & Earnshaw's book (this one: https://www.amazon.com/-/dp/0750633654) from the nearest university library, it has a chapter on nucleogenesis and cosmic and geologic abundances.
Neutron star merger is a rather energetic event, ejecting copious amounts of matter. Dying low-mass stars (like the sun) eject their outer envelope, forming an expanding nebula.
Is it because all heavy elements present when Earth formed sank to the center?
That would make sense, but I've assumed that since we can mine gold, that's not what happened. If all the gold fell from the sky, that would explain things.
I don't like that these don't also take into account secondary events (like non catastrophic fusion nucleosynthesis, or radioactive decay). And maybe some indication that nearly all helium on earth is not primordial, which is not the case in the universe.
As you walk your way down the table is there a correlation with elements being more “recycled” for lack of a better term?
Ie. H and He are the basest elements and then everything else is formed through increasing amount of processes? Having a hard time articulating this one.
The process that drives stars is fusion, which turns light elements into heavier (strictly greater atomic number) elements, up to iron. Elements heavier than iron are created in supernovas, neutron star collisions etc.
Many heavier elements are unstable and will radioactively decay into light elements.
The most stable element is iron, in terms of having the optimal binding energy (you gain energy for fusing lighter elements into iron, you gain energy for splitting heavier elements into iron). If proton decay doesn't exist, then the trend of all matter would be to turn into iron. If proton decay does exist, then iron itself would decay to less stable elements because the protons in iron would disappear, and the neutron-rich lighter elements would be subject to radioactive decay.
It is unknown how stable our stable nuclei are. Bismuth-209 was long listed as a stable nuclide, until a decay event was observed in 2003, establishing its half life of about 10¹⁹ years (by contrast, the universe is about 10¹⁰ years old).
Memory is a bit rusty on this (30 years since I did nuclear physics) but elements have stable and unstable isotopes (with the same number of protons and a different number of neutrons). E.g. Carbon 12 and 13 are stable and Carbon 14 is unstable (half-life 5730 years). An atom will keep decaying until it reaches a stable form. Then it will stay like that until some nuclear fusion or fission event occurs.
For heavy elements this usually means a terminal at the 206, 207, or 208 isotopes of lead or thallium-205; radioactive isotopes smaller than that usually quickly hit a "nearby" stable isotope.
They're decaying to a stable middle region. In theory, they're decaying into nothingness, but that's like saying "in theory, things reach absolute zero".
> It certainly makes sense: you need more complex machinery to form more complex elements.
Probably time as much as machinery: in the hyper-energetic early universe, it would have been harder for matter to get close together long enough to form large atoms. (I just push back slightly because I think complex elements aren't really complex, just big, requiring a stable environment for 'assembly'—but I am a mathematician, not a physicist or chemist, so I wouldn't be surprised to be wildly wrong.)
It would be cool to see this made into a series of pie charts (one for each element) where the relative area of each pie chart is dictated by the relative abundance of each element.
100+ pie charts? That sounds even worse than just one pie chart -- though given H and He make up ~98% of everything, squeezing the data into one pie chart would make it extra-awful.
I don’t see how it would be awful. It would give the same information but also show how much matter is from each source. Vector graphics eliminate resolution concerns. Just zoom past hydrogen if it’s taking up 98% of the screen.
Edit: to be clear: the reason it would “be cool to see” is because it’s visualizing data. It’s what graphs are for. I don’t care about the pies of the pie charts. I care about being able to see the relative quantity of the colors and to also see the distribution of discrete element quantities in one image. There are many ways to do this. If you have a better suggestion, suggest it.
So you want to see the ratio of origin of all elements, but grouped by element? (one chart per element I think you said originally).
This is what the image in TFA actually has -- each element has one or more colours within its rectangle, and I assume that the proportion of each colour reflects relative provenance for that particular element.
Yes, but the information of the abundance of each element is not present. If that information was added into this plot then the relative amount of each color would be the relative abundance of the origin of elements.
I don’t see how an extreme distribution makes the representation less useful. See: vector images. In fact, the large disparity is relative abundance of elements is why it would be even more useful. A periodic table says next to nothing about how much matter has gone through nucleosynthesis since the big bang. You could show that with one pie chart, but then you lose the information about the distribution of masses. You haven’t given a good reason why it wouldn’t be useful to have all three pieces of information in one graph.
Oh, I expect people come to HN to see interesting things.
"It would be nice to ..." may not fit into that category.
Anyway, as I understand it, on an A4 infographic, you'd be expecting to see one pie chart (H) taking up 3/4 of the page.
Almost all the other 1/4 of the page would be taken up by an He circle.
Then you'd have a (still recognisable as a circle) for Oxygen, at about 6mm wide, the next would be 4mm wide for Carbon.
After that I'd guess we're at ~1mm pie charts for Neon, Iron, Nitrogen.
After the first 7 pie charts, each subsequent pie chart would be the size of a pixel (or sub-mm on a printed page). So it'd look like a hundred or so tiny dots.
Have I misunderstand the visualisation you're describing?
You seem to miss the point of HN, or in fact the very concept of communities in general.
Why do you think the graphic would be printed? If printed, why would it be smaller than 20 feet across? I am confused by these unreasonable assumptions.
This chart brings up the question of HOW exactly each element is created...
A long time ago, in Alchemy, there was the idea that certain elements could be transformed into other elements by alchemical processes. This idea, back then, was called "Transmutation".
Now, scientists of today know transmutation as possible, but only with select heavy elements, and only in atom smashers/cyclotrons/large hadron colliders -- call them by whatever name you will.
Also, there exist radioactive elements which, over (usually!) very long periods of time, decay or transmute, into lighter elements.
The common theme, in all of the above, is radiation.
In other words, radiation is somehow linked to the transformation of elements.
Now, with that in mind, if I may posit an impromptu hypothesis, and that is, not all radiation is created equal...
In other words, you have alpha rays, beta rays, x-rays, gamma rays, etc. Or call them particles instead of rays if you prefer.
Anyway, Each of these particles/rays has different penetrating power. An alpha ray/particle (if I recall correctly) is blocked by a piece of paper, but it takes yards and yards of cement or metal to block a gamma ray -- and that's even if you can do it.
But, here's the thing.
Usually we see heat in the role of transforming things, not so much from element to element, but from compound to elements (i.e., refining iron from iron ore).
So, with that in mind, here's the hypothesis:
Perhaps heat -- is actually radiation, but at a lower scale/magnitude/area of effect/penetration-of-space/ability to traverse a distance, power.
In other words -- heat is localized radiation.
Or, phrased another way, radiation is heat -- but sent outward to a non-local distance.
So why is radiation "cold" at a distance to us humans?
Well, remember that that's a scale effect (the underlying energy should have the same pattern regardless of scale, that is, scale could be much smaller), and the Inverse Square Law (https://en.wikipedia.org/wiki/Inverse-square_law) still applies.
So, heat as localized radiation, and radiation as larger-in-scale-with-respect-to-distance heat.
Why are there 4 fields (strong nuclear, weak nuclear, electromagnetic, gravity).
What even is a 'field'.
Why does gravity affect the other three?
What is time? What is space? What is quantum entanglement?
Why is there a universal speed limit?
Why do you need an 'equal and opposite reaction' to gain momentum, why can't you just convert angular energy directtly into linear energy in a single direction?
Why is there a universe at all, instead of nothing?
Etc, etc.
But as far as 'what is heat', you should read more, or just google your questions.
You might be surprised at how many other people have asked the same questions, and then set out to answer them, but with evidence. It's called "Science".
>Why are there 4 fields (strong nuclear, weak nuclear, electromagnetic, gravity).
Why is it that certain pairs of things in the universe can influence each other at a distance, and other pairs of things cannot? (For example, a musical instrument resonating at the fundamental pitch of a wine glass can vibrate and/or potentially shatter the wine glass).
Why are there 4 fields? Well, potentially there are an infinite number of fields -- but each one's "sphere of influence" is "local" to a specific scale. Some span the smallest units of distance; others span much larger scales...
>Why does gravity affect the other three?
Why do non-prime integers have multiple factors that divide into them; Conversely, why can larger integers be made by multiplying two or more integers; Think of this with respect to vibrations; with respect to waves; if something in the universe is affected by or affects something else, generally speaking it's because they vibrate sympathetically at some level or other. Also, it's possible that the other three forces are influenced by gravity because gravity is the fundamental constituent of them, that is, they are all created by gravity in various different configurations, just like larger integers are created by multiplying smaller ones, or larger patterns are created by smaller ones.
In other words, strong nuclear, weak nuclear, and electromagnetic forces -- ARE gravity -- in its various modes/oscillations/vibrations/patterns/configurations/structures, etc.
Phrased another way, Gravity is the Y Combinator of the other forces, the central low-level pattern from which the other higher-level patterns are built...
>What even is a 'field'.
In classical physics, you have the particle/wave duality. Basically, one is the other, depending on frame of reference.
That particle wave duality (I've determined) is actually a
particle/wave/field TRINITY.
That is, particles ARE waves (depending on how you look at them), waves are particles (depending on how you look at them), BUT ALSO waves are fields (depending on how you look at them), and fields are waves (depending on how you look at them), and fields are particles (depending on how you look at them) and particles are fields, again, "depending on how you look at them".
Google "Starlings". A single starling at rest is a particle, in motion, it's a wave, and many of them together moving in unision, that's a field.
Also (and this is the advanced lesson), you can have various degrees of recursion in this, for example, a whole field of starlings could be viewed as a single particle, then that could comprise multiple particles if teamed up with other fields of starlings, and then those things could move like wave.
Think nested particles/waves/fields -- inside of other particles/waves/fields.
Also, the smallest unit of space (to implement all of the others), DOESN'T NEED TO PHYSICALLY MOVE; that is, it only needs to state-change, like a pixel, if it were a magnet, it could change from a North Pole to South Pole (or possibly neutral), if charged, the charge could go from positive to negative and back, if a region of force, the force could push one way and then the reverse, etc., etc.
But the smallest units of space... DON'T NEED TO PHYSICALLY MOVE. There's absolutely no motion on a TV or monitor screen; these are ILLUSIONS created by the mind's observation...
>Why does gravity affect the other three?
Asked and answered. See above.
>What is time? What is space? What is quantum entanglement?
You forgot "distance" and "velocity". What are they?
Space can be defined in terms of speed (velocity) and time, i.e., if you travel 60 MPH for one hour, you've travelled one mile.
Time can be defined in terms of distance travelled relative to speed (velocity) -- if you travel at 60 MPH, and you don't know what time it is or when you started, but you know you've travelled 60 physical miles, then you know you've travelled for one hour.
And of course, speed (velocity) can be defined in terms of time and space.
But the problem is, try to separate one from the other two and define it by itself -- you can't do it. You need the other two to define the third one. Which means that they are all interrelated, and possibly aspects of the same basic thing...
>Why is there a universal speed limit?
There is none; this is fake news; "speed" is always relative to local distance, which is relative to scale. In the time it takes your local watch's second hand to move one second, Cesium will have osciallated 9,192,631,770 times in that second. Elephants move faster than Ants, but they're also physically larger. The Earth rotates at 430 meters per second, much faster than an Elephant walks -- but the Earth is much bigger in scale. The Earth revolves around the sun at 30 Kilometers/second but again, that's a larger scale. The Sun's motion in space, relative to the gravity well in our galaxy which it revolves around will be much faster than that, but again, it's relative to scale.
>Why do you need an 'equal and opposite reaction' to gain momentum, why can't you just convert angular energy directly into linear energy in a single direction?
If you were in outer space, pitch-black empty space, and there were no planets, stars, or other celestial objects by which you could compute your rate of speed, how would you know that:
A) You were stopped?
B) That you weren't going at some rate of speed?
C) That you weren't travelling at INFINITE SPEED?
In other words,
1) HOW WOULD YOU KNOW YOUR RATE OF SPEED, and
2) IF YOU COULD NOT KNOW YOUR RATE OF SPEED, THEN WHAT WOULD THE DIFFERENCE BETWEEN THIS STATE, AND THE STATES OF BEING STOPPED, TRAVELLING AT A SPEED, AND TRAVELLING AT INFINITE SPEED BE?
In other words, it's paradoxical. In this state 0 speed (stopped) = some speed = INFINITE SPEED. How would you know the difference? You couldn't...
Say it with me, "Speed is RELATIVE to a FRAME OF REFERENCE", if you're moving at a rate of 60,000 MPH away from a planet, that planet is equally-and-oppositely moving at a rate of 60,000 MPH away from you (and it didn't invest any energy, not one drop, to gain that speed! <g>)
>Why is there a universe at all, instead of nothing?
Why are there billions of web pages, book pages, and other written documents in English, and yet, there are only 26 characters in its alphabet (or 52 if you count lower-case letters). Heck, 53 if you count 'space' as a character.
That's one heck of a lot of things constructed from so small a set of repeating entities. <g>
Etc, etc.
>But as far as 'what is heat', you should read more, or just google your questions.
I quote to you Socrates: "The true knowledge consists of knowing that you know nothing".
>You might be surprised at how many other people have asked the same questions, and then set out to answer them, but with evidence. It's called "Science".
Yes, but Science and all Scientific Evidence -- must be consistent with itself.
Well, this brings up an interesting (to me at least! <g>) philosophical discussion about Principles Vs. Accolades, specifically as they relate to Science and Scientific Thought, in this day and age.
A Principle is any cause-effect relationship that is guaranteed to work consistently (e.g., Newton's Third Law).
An Accolade, on the other hand, to explain it, it requires the point-of-view of someone who has already attained one -- so let's use Albert Einstein as that first person point of view...
From Einstein's perspective then, things look like this: "Hey Einstein, you won the Nobel Prize, now you get these awards, honors, fame, privileges and benefits (and whatever else you get!) as a result of <papers written and/or other actions taken> to advance science, etc., etc."
An Accolade exists solely as privilege of some sort or sorts, and exists solely in the social sphere.
An Accolade might exist as fame, power, money, respect, influence, being attractive to the opposite sex, and/or series of privileges, such as being able to get an academic paper read, published, or combinations of one or more of the above, etc.
They're nice and all (I am not knocking them), but they exist on the other side -- as the EFFECT -- of having engaged in the work that someone like Einstein engaged in.
Again, I am not interested in Accolades.
To understand this, let's talk about Principles.
Principles do not just exist in physics, in science -- principles exist across the whole spectrum of any subject that can be learned, from business and salesmanship to law and public policy, from finance and economics to psychology and human relationships, from writing and language to even such areas as comedy and movie production!
In short, there is no shortage of Principles that can be learned, in every field of human endeavor.
Having/Knowing/Understanding the right principle or principles for a given situation -- is not unlike having a pool table, and needing to make a specific shot, put a specific ball in a specific pocket.
The pool table is not unlike the current state of the Universe, and the ball to be sunk, in the pocket that it is to be sunk in, is not unlike the next succeeding desired state of the Universe.
Well, if the principles applied are the correct ones (in pool table terms, this would be the correct angle and correct velocity applied to the cue ball via the cue, pre-calculating all of the bounce angles and patterns of other balls), then whoever applies the correct principle(s) should get the change to the Universe desired, guaranteed every time, no questions asked!
Such is the power of Principles -- correctly applied.
You can get anything and everything you want in the Universe (I really believe that), but you must know the correct principle or principles, and you must know exactly when and under what circumstances to apply them ("timing is everything"...)
You see, anything that an Accolade could or ever would do for a person, a person could get by a different route, if they knew the correct principles, and when to correctly apply them...
Accolades fade and disappear as enough time passes, much like fame does.
Principles, on the other hand, are eternal.
They do not change over time, at least, not if they're true principles.
Also, with the right Principles applied correctly, you could get as many Accolades as you wished -- but the reverse is not true!
Accolades themselves do not make the recipient any more knowledgeable about, nor able to apply Principles!
Phrased another way, "Wisdom avoids vanity".
Now, with respect to physics papers, there are probably people today in physics (like Ramanujan was in his day in mathematics) who are utterly brilliant -- but their work is never read by mainstream physicists!
Why?
Well, think of physics papers in this day and age as not unlike what makes clothing fashionable...
In the fashion industry, in order to create a best-selling new fashion, the rule of thumb is that you have to be slightly different, but not too different, from last year's best-selling fashions.
Applied to physics (or science in general then), you have to be slightly different, but not too diffrent, from what's currently popular in the mainstream.
In other words, writing a scientific paper (if you want it read, published, lauded, etc., etc.) is no different than a popularity contest.
Sort of like, to quote the Zoolander movie, "You duplicate, then you elaborate".
If I were going to write a paper and I wanted to make it popular and well-received, first I'd duplicate (all of the trendy ideas and theories of the day, and that would be about 95% - 98% of the paper! <g>), then I'd elaborate (add about 2% - 5% of something novel-sounding and attention-getting, regardless of whether it was logical, compatible, or even well-thought-out, or even the baseline assumptions were well-thought-out...).
But unfortunately, I have several "mental blocks" towards such an act... some of them are called: Ethics, Morals, Integrity, Honesty, Virtue, Values, Lawfulness, "Not wanting to waste other people's time by creating more B.S. for the world", etc.
You know, your basic mental illness! <g>
I claim being intellectually handicapped in this area! <g>
So, to sum it all up, people can seek Principles (and not write papers!), or they can seek Accolades (and probably have to write a few papers, and do god-knows-what-else! <g>)
Principles are a superset of Accolades, because with one, you can get the other, but not the other way around!
Accolades are a subset of Principles (if set A is a superset of B, then set B must be a subset of A).
So, that is why I care about Principles, not Accolades.
And that is why I don't really care to write papers... Who am I trying to impress, and WHY (key point!), WHY am I trying to impress them? What would I be trying to get out of that equation? Wouldn't there be another way to get those things via the proper application of the correct Principles?
As far as I know, Elon Musk doesn't write any papers, yet he has applied Principles (both in Science and Business) correctly(!)
Does he lack for any form of social privilege that might be bestowed by an Accolade?
?
"Give me a lever long enough and a fulcrum on which to place it, and I shall move the world." (<- Example of Principle)
The theory you've written is utterly crackpot, but the general principles are actually pretty close to our modern understanding of physics. Radiation is highly-localised jkace that can travel a long distance without diffusing (hence why it has distant effects), whereas heat is jkace spread out between a large collection of particles that easily spreads to nearby matter and escapes as low-energy electromagnetic radiation (hence why it has short-range effects).
Oh, and jkace is usually called "energy". We're not really sure what it is, but we know so much about its behaviour we can describe it mathematically.
And by the way, the reason not all radiation is created equal is because "radiation" is a very broad term; it's like saying "not all fruits are created equal", except if you also count orange squash as a type of fruit. X-rays and gamma rays are just very bluer-than-blue light (the distinction in names is based on whether they come from X-ray tubes or radioactivity), beta rays are just fast electrons, and alpha rays are just fast "middle-of-a-Helium-atom"s – which is why alpha rays can barely travel through air, beta rays can't travel through your car and gamma rays can travel through anything that's translucent to gamma light.
How does a "merged" neutron star, "unmerge?" Or is most of the Au of the universe tied up in neutron stars? And how does that work given that neutron stars are mostly... neutrons?
A neutron star "merger" is a collision between two of the hottest, densest objects in the universe that are still objects. These collisions are incredibly messy and energetic. Stuff gets blown everywhere - a lot of stuff.
Once freed and blown out into space, the remaining neutronium is incredibly unstable without the intense gravitational pressures holding it together. It will rapidly decay into relatively stable material.
https://upload.wikimedia.org/wikipedia/commons/3/31/Nucleosy...