It's also worth noting that this is not an extract from a technical paper, but from the "Canadian Presbyterian", apparently a Christian journal; and not written by a professional scientist, but "Principal Leich". Someone feels the need to justify including information from such a source by prefacing it with: "Principal Leich seems to be perfectly familiar with mechanical science."
So just keep in mind, what's written does not necessarily represent the scientific consensus, but the opinion of an enthusiastic amateur.
That said, given the explanation of the conservation of energy in the opening paragraphs, I wonder if this the original purpose was actually partly to convince the readers of The Presbyterian, presumably religious people familiar with the Genesis accounts of creation, that "young earth" creationist theories are incorrect: i.e.:
1. If the sun were burning a fuel -- even coal, one of the highest-energy fuels we know* -- it would be less than 5000 years old.
2. If rather the sun is incandescent, then it is at minimum 100 million years old.
3. Either way, 6000 years old doesn't fit.
(* I have no idea if this would have been true in 1863 or not)
The 6000 year claim does not appear in Genesis, I do not know enough history to say but it's possible that YEC-ism is based on a modern invention of interpretation.
There are long chronologies in Genesis that include, "A lived for X years and begat B. B lived for Z years and at C." If you assume these are contiguous and precise, and that the meaning of "year" hasn't changed, and that Adam was "born" on day 6 of creation, and the universe was created 6*24 hours before that, then you can calculate when various Biblical events happened -- including when the world was made. Ussher made his estimate in the 1600s; according to that Wikipedia article, Rabbi Jose ben Halfata made an estimate as far back as the 2nd century AD.
But I'm pretty sure even in Ussher's time, there were lots of Christians who said that those kinds of calculations weren't necessarily useful or accurate: that the book of Genesis wasn't trying to teach people Geology, but Theology.
Read through the Babylonian creation myth [1], in which the Earth is created by the carcass of a murdered god ripped in half and humans are made from the droplets of blood of another god "to serve the gods", and ask yourself: "What is the world like? What is my place in it as a normal human being?" Then read Genesis 1 and ask yourself the same questions. You'd reach quite different conclusions.
Well, naturally it could not appear in Genesis, lacking any reasonable epoch point relative to which it could be defined. The 6000 year figure, at least in the Anglosphere, most likely derives from Archbishop James Ussher's genealogical calculations in the 17th century [1]. However, I don't think that has been any sort of common belief before the modern YEC movement.
Having grown out of a young-earth Creationist religion, I can say that the 6000 year claim is based on a rather fanatically literal interpretation of Genesis and the surrounding histories. Reading the genealogy of Genesis 5 and trusting that the ages are accurate, that they skip no one, and that Adam was literally created by God in year 0. With some simple addition, that genealogy gives a birth date for Abraham of about 2000 years after Adam. From there, a literal/historical/grammatical hermeneutic brings you to the Exodus and iron age histories that can pretty confidently assign real dates. Maybe it's just the indoctrination I grew up in that still empathizes with the ability to read "After Noah was 500 years old, he became the father of Shem, Ham, and Japheth" and say "yep, there's another 500 years on the chronology" and imagine that Christians have always done that.
"According to Hebrew time reckoning we are now in the 6th millennium. The Hebrew year count starts in year 3761 BCE, which the 12th-century Jewish philosopher Maimonides established as the biblical date of Creation."
YEC was always based on a lot of supposition and poor science and was mostly a reaction to the rise of evolution as a replacement explanation for the origin of life. Whether you believe Genesis or not YEC doesn't hold up when examined critically.
Right, but this was written in 1863, and Origin of the Species had just come out in 1859. (And there were various other evolutionary theories before then.) Like I said, it's just a guess, but the question of the age of the universe would have been very fresh at the time.
Interesting to read. The Sun is referred to as 'he' and people were just beginning to understand how heat energy and mechanical energy could be transformed into one another.
"He has enlightened our globe from one generation to another without any apparent diminution of strength, and we have formed the instinctive belief that no limit in the past or any in the future can be assigned to his functions. No proof of progress or decay has been detected ; and it has been thought that nothing but the fiat of the Almighty can quench his rays. Principles have now been recognized, however, which enable us to assign limits, and to show that he has not shone from a past eternity, and that he has a limited existence as an incandescent body. This limit assigned to the solar system forces us to recognize the hand of a Creator."
"The meteoric stones that sometimes fall to our earth may be regarded as balls, but moving with much greater velocity. They strike against our atmosphere with so much force that the force is converted into heat, so intense that they glow or become incandescent. .... Assuming that the heat of the sun has been kept up by meteoric bodies falling into it, and proof has been given of such fall, it is possible from the mass of the solar system to determine approximately the period during which the sun has shone as a luminary"
"Limits can be set to the fuel of the solar system, and therefore limits can also be assigned to the existence of the sun as our luminary. The limits lie between 100 millions and 400 millions of years. These are enormous periods, but still they are definite. The mass is so great,and the cooling is so slow, that, even on the supposition that no fuel was added, it might be five or six thousand years before the sun cooled down a single degree."
I wonder if they picked pronouns for the planets in accordance with the associated gods of Greco-Roman mythology? IIRC, the Greco-Roman sun gods were all male (e.g. https://en.wikipedia.org/wiki/Helios).
If I'm correct they'd use male pronouns for the sun, Mars, and Jupiter; and female pronouns for Earth, the Moon (Luna), and Venus.
Germanic languages, of which English was one, have this too and "sun" is Germanic in etymology. Most PIE-derived languages had this at one point but some, including English, lost it.
In German the sun is female though (and the moon male). In French the sun seems to be male and the moon female (I don't know the language though, just looked it up), so maybe these are traces of the French influence into the English language?
Old English, i.e. the language of Beowulf, is a Germanic language. With the Norman invasion, English became heavily influenced by the Romance languages. So English has roots in both both old German and old French.
One place you see this is in terms relating to food. Words relating to rustic activities like agriculture and raising animals such as "cow" tend to have German roots. While culinary words like beef and veal tend to have french roots.
It seems that sun was feminine and the moon was masculine in Old English up to about the 16th century:
"sun (n.) [...] Old English sunne was feminine (as generally in Germanic), and the fem. pronoun was used in English until 16c.; since then masc. has prevailed." [1]
"moon (n.) [...] A masculine noun in Old English." [2]
Just an interesting bit of human psychology: a motorcycle could be either gender as it's strongly analogous to a horse, but a car is always female.
In languages with gendered nouns, objects which can have humans inside of them (e.g. cars, boats, houses) are almost universally female (presumably because females have wombs), and this leaks into English pronouns as well.
>... a motorcycle could be either gender as it's strongly analogous to a horse, but a car is always female.
In Brazilian Portuguese, we use masculine pronouns for cars ("o carro"). Same goes for boat ("o barco") and plane ("o avião"). This can also be seen in Spanish ("el coche", "el barco", "el avión").
I believe that the gender these things are referred to in languages with gendered nouns is more linked to the etymology and development of linguistics than psychology, although it is very likely that the later has some influence as well.
It’s interesting because English has not used grammatical gender for inanimate objects for quite some time (aside from a few exceptions such as ships). I don’t think I’ve seen the sun referred to as “he” in other 19th century writings.
In old Swedish (~19th century) nouns were divided into three grammatical genus: femininum, masculinum and neutrum. Dead objects could be referred to as either he or she:
- earth, sun and time are feminine words and can to this day still be referred to as 'she'
- heaven, road and stone were referred to as 'he', although this has disappeared from modern Swedish.
Icelandic retains the full 3-gender system to this day, and it’s generally incorrect to refer to gendered inanimate objects as “it”, rather than “he” or “she”.
Same with German, which has a neutrum genus but sometimes even uses it for people (the child, das Kind, the girl, das Mädchen, the victim, das Opfer, ...)
The number of inanimate objects that are not gendered must be pretty small. The sun is female (die Sonne), a street is female (die Straße), cars and houses are neutrum (das Haus, das Auto)
Was this in classes for English as a second language?
Because, as a native English speaker, this seems like misinformation to me, perhaps partly influenced by your teacher having a first language where nouns do still have gender.
This a weird memory to be honest. Yes,you are right, English is a second language and normally sun and moon would be 'it' and not 'she' or 'he'.The teacher was too good to get mixed up when it comes to genders but because it was more than 20 years ago,I've got a feeling that there was more into it.Maybe it is how it used to be in onld English or something.
As an native speaker I think things that are personified have an aura of gender. Impersonal objects do not. Ships are female for instance. And you use the proper pronoun. The earth is feminine but you don't.
Well, coincidentally, helium was discovered in 1868, just a few years after the OP article was written, via detection of a spectral line in sunlight that didn't correspond to any previously known element. Hence the name. Of course they didn't yet have any idea about stellar nucleosynthesis and helium's role in it.
It doesn't matter that the article is bollocks. It is reasoned bollocks. That is basically what science is all about! I would prefer if there was some more working shown to back up the article but it seems to imply that some might be available rather than just simple assertions.
We live in a world where some people genuinely seem to think that a newer version of a mobile phone comms medium can cause a disease that we know is caused by a virus. These same people seem to be aware of other viruses and bacteria and their effects just as well as any other layman. It is only this particular combination that is the current "conspiracy".
We need the likes of Scientific American to carry on their work of delivering the best descriptions of the rather odd workings of the world and the universe. They are what the rest of the media turn to when they need to cover something they don't understand.
The sun does not burn coal but frankly that is less embarrassing than admitting that our best theories can't explain where most of the sodding universe actually is. We are so advanced that we do not know where 85% of matter is hiding out. lol
I'm not sure it's helpful to describe this 1863 article as "reasoned bollocks"
In this same timeframe Kelvin supposes the Earth cannot possibly be billions of years old because it's warm underground. You can measure and verify that the Sun can't be keeping the Earth this warm, if it was just down to the Sun this place would be uninhabitable. Nothing could be this warm after cooling down for billions of years with just the Sun pointed at it. Kelvin supposes 100 million is an upper limit, and in later life committed to 20-40 million with 20 more likely. Biologists spluttered because Evolution can't explain cells to chimpanzees in 20 million years, it's not long enough. But they did not have a coherent explanation for why Kelvin might be wrong...
Radioactivity is the answer, something that would not be found until the end of the century, and it would take until the start of the 20th century for somebody to realise that this makes Kelvin's age-of-the-planet calculation hopeless, if you assume the planet is slightly radioactive (which it is) then it can easily be billions of years old and the biologists are right.
> You can measure and verify that the Sun can't be keeping the Earth this warm, if it was just down to the Sun this place would be uninhabitable.
This is somewhat misleading because the Sun is pretty much the sole energy source for keeping the surface of the Earth warm:
> Despite its geological significance, this heat energy coming from Earth's interior is actually only 0.03% of Earth's total energy budget at the surface, which is dominated by 173,000 TW of incoming solar radiation. [1]
The problem posed by Kelvin was the the interior of the Earth was too warm, which may affect long-term habitability because plate tectonics plays a role in regulating the atmosphere's CO2 levels (or so I've heard), but of course nobody at Kelvin's time knew that. Kelvin wasn't asking "Why isn't the Earth a dead planet?"
Yup. Bang to rights gov, I was under the impression that insolation isn't enough to do 275K on the surface (ie temperature above freezing) and thus you couldn't really live here, but actually I was wrong.
Actually, main thing that kelvin got wrong is that the Earth has a liquid mantle. Convection in the mantle means that the surface receives more heat from the interior and takes longer to cool down to the present temperatures. Radioactive decay inside the earth also adds to the age of the earth but not as much as the convection in the mantle does.
That's fair, a "convective mantel" model which accepts Kelvin's other assumptions gives 2-3 billion years, so it's at least ballpark compatible with biology. I think you'd have struggled to hide the mismatch eventually but it does pass a laugh test unlike 20 million years.
Unlike radioactivity, Kelvin could have considered convection and so that's his fault.
The mantle is (mostly) not liquid. It can transmit shear waves, which a liquid cannot do. The convection is occurring in a solid, by plastic deformation.
What's sad is that Kelvin could have used his reasoning to determine that this convection must have been occurring, and from that inferred that continents likely drift around, driven by convection. But he was driven by religious convictions to try to demonstrate evolution couldn't have occurred because there wasn't enough time.
I don't understand how convection can increase the time to cool down. It seems to me that the higher temperatures closer to the surface facilitated by convection would lead to faster cooling.
Faster cooling, but smoother gradients. It means that if you go down a hundred miles, it will be warmer, but the entire center of the earth will be closer to the same temperature. If you assume a solid, you assume a certain constant thermal conductivity, as Kelvin did, even though with a liquid, that's not true. Basically, he assumed that the heat was diffusing slowly, and that it couldn't go above a certain temperature at the core (i.e. not a gas or liquid), and so you had hard limits on the total reservoir of heat in the planet and could calculate a linear fit on it. It turns out the effective thermal conductivity of the center of the earth is much higher than the thermal conductivity of e.g. continental crust.
> If you assume a solid, you assume a certain constant thermal conductivity, as Kelvin did, even though with a liquid, that's not true
I think the liquid is a red herring here. The important thing is a that there are two layers with different properties. Would work just as well with an inner highly conductive solid.
WIthout convection the earth as a whole takes longer to cool down but the surface layer cools faster. In an earth with a convective mantle the earth as a whole cools faster but the surface layer cools slower (because it is receiving more heat from the core).
This article helped me understand that back in the day: www.blc.arizona.edu/courses/schaffer/449/England%20-%20Perrys%20Neglected%20Critique.pdf
It delights me how scientific discoveries can be so interconnected. It never occurred to me that Marie Curie's work indirectly helped prove Darwin's theory of evolution
To be fair to Kelvin, it was a reasonable opinion at the time:
1) Half of the aviation pioneers died trying.
2) The Wright brothers were truly overachievers, devising a control system, early aviation engine (1903) and wind tunnel.
3) Producing light-weight, reliable and powerful aviation engines took over 20 years. The Atlantic crossing only became survivable after the Wright Brothers made the Whirlwind J-5 radial engine (1925):
He didn't say things heavier than air can't fly. Just that we can't make them... (and at the time, we didn't have any success making them - we did however had great success with "lighter than air" air displacement vehicles, namely hot air balloons).
Consciousness is clearly a different kind of problem than flight, for one thing it is possible to tell if something is flying buy not possible to tell if it is conscious.
It would be very presumptuous to categorically rule out that humans will create conscious beings. We don’t know how to do it yet but if nature did it, why wouldn’t we?
Assume a spherical planet. OK an ablate spheroid. OK a ...
Now assume Lord Kelvin is talking bollocks. Just because you invent "really cold, bordering on quite nippy" doesn't mean you can overlook things like half lives and red shift. If Lord Kelvin lived now I suspect he might have other conclusions - he evaluated the evidence available at the time.
I was deliberately provocative and I'm glad I was. I've got far better responses as a result. I never thought to mention Kelvin and you have dived in and filled in that gap.
The article in SA was and is absolute bollocks. Bear in mind that your and my definition of bollocks may be dissimilar and I am not being disrespectful. The article is very short and does not provide working. It is of its time and I suspect the working is available somewhere else. It gives us a short glimpse of popular science writing 150 odd years ago.
You might want to take another look at the usernames involved.
I'm not claiming that "an ablate spheroid" was correct usage. I'm pointing out that the response, "to 'ablate' is to erode", is a non sequitur. It is relevant neither to its parent comment nor to the comment in which it appears.
>I'm not claiming that "an ablate spheroid" was correct usage. I'm pointing out that the response, "to 'ablate' is to erode", is a non sequitur.
Which is still a wrong thing to say and a bad argument.
You appear to be arguing something like "I couldn't mean ablate, since it doesn't fit the context, so why mention it". Well, whether you meant it or not, you did write it, and you could very well have done it because you thought it meant "oblate".
This doesn't make the correction a "non sequitur" in any way. On the contrary, it's very relevant: it provides the actual meaning of the term used (whether it was used as a typo or because you didn't know the correct meaning).
And that's too many words for a non-issue. "Ablate" was the wrong word for your intended meaning, somebody pointed it while also explaining what it means. End of story.
> You appear to be arguing something like "I couldn't mean ablate, since it doesn't fit the context, so why mention it". Well, whether you meant it or not, you did write it, and you could very well have done it because you thought it meant "oblate".
This is a pretty stunning thing to write after I've already had to point out to someone else that I didn't write the sentence in question. Did you read my comment before responding to it?
Now consider this sentence:
> "Ablate" was the wrong word for your intended meaning
If I respond "but this makes no sense; to 'wrong' is to unfairly cause harm", would that be a good argument? Would it constitute any evidence of any kind about your usage of the word "wrong"?
Obviously not, but it's exactly the same as the original argument I responded to, "to 'ablate' is to erode".
I do admit that I hit o instead of a, I have no idea why because I am familiar with the difference between the two words, which are not remotely related in meaning.
I'm gerdesj who actually committed the original mistake and not the other person who dived in.
I wouldn't even say it's nonsense. Edit: just realized the precise word you used was in fact 'bollocks'. I wouldn't say it's that either.
The logic behind the sun not burning a fuel like coal is entirely sound. From there an alternate theory is proposed based on the limits of understanding of the time. Not as fact, but as a best guess theory that fits the evidence at that point. The theory was wrong of course, but it was a step in the right direction.
"The logic behind the sun not burning a fuel like coal is entirely sound"
That is precisely why I called it "reasoned bollocks" - perhaps a bit colourful for HN. As you say the theory was wrong but the article was describing current theory at the time and is of course ... science.
I really am praising a long running science magazine as best I can. I am a massive fan.
You're still being too hard on it. There's a clear recognition that combustion isn't sufficient. And the only other option seemed to be gravitational accretion.
And it remained an open question until at least 1920:[0]
> Around 1920, [Arthur Eddington] anticipated the discovery and mechanism of nuclear fusion processes in stars, in his paper The Internal Constitution of the Stars. At that time, the source of stellar energy was a complete mystery; Eddington correctly speculated that the source was fusion of hydrogen into helium, liberating enormous energy according to Einstein's equation E = mc2. This was a particularly remarkable development since at that time fusion and thermonuclear energy, and even the fact that stars are largely composed of hydrogen (see metallicity), had not yet been discovered.
Yeah, makes sense. Just a different way of describing the same thing. Sound logic that led in the right direction if not (yet) to the right destination.
More generally, probably a useful distinction to keep in mind, between when science is offering us a direction and a theory vs when we really do have the evidence required to be fairly confident we're at the destination.
Of course even then there are often deeper layers—floors within the destination building say, to torture the analogy. But that kind of distinction is different from the one between a guess that fits the evidence so far and something that is reasonably known.
It seems very anachronistic to describe it like that. Like calling the Apple I a failure for selling a couple hundred and ridiculously underpowered for not even having a 1 GHz processor. People make comments like that now and then, and it's just odd.
My university library had these bound up and sitting on the regular shelves, going back to the mid 19th century. The early ones came out a couple of times a month and the format was broadsheet which is a weird way to read a popular science magazine but I suppose that's how people rolled back then. You could definitely fold a single issue into several sizable hats.
Now, imagine video with the scientist narrating this new finding (Sun is 400m years old, and gives heat and light because of meteors falling on it) is being removed by youtube, because these views are so dissenting with prevailing opinion of the world being 6000 years old max, and could harm minds of a general population, turning people away from God .
The issue there might be more that there is a single “publisher” in that media that gets to do all the gatekeeping. I’m sure American Scientist 1863 would have declined to publish lots of ideas, but didn’t have the market cornered.
[Please move away from the DV button - I like to encourage discussion around here]
You forgot the conclusion. The prevailing opinion about the world's age is not 6000 years. I think some fundamentalist Christians might try for 4004 BC so 6000 years ... ish but I don't even know anyone who subscribes to that nonsense. I'm sure there are some who do but they are not my mates. They are certainly not general population.
It wasn't really a controversy or dogmatic issue to average Christians until the early 20th century. Trying to argue with a Young Earth Creationist on scientific grounds is super pointless - literally everything can be either dismissed because you weren't present, or reinterpreted to fit the viewpoint. I would know because that used to be me.
It's also highly unlikely that you'll successfully argue with them from a theological/hermeneutical perspective either. If you'll forgive me entering into a major time controversy here: a young earth creationist, and many evangelicals, place the original Biblical text as penned by the human author at a nearly deified level. Unless the text is blatantly poetic, even in translation, or explicitly labelled a parable the text is assumed to be literal.
The human author of scripture is basically assumed to be, more-or-less, possessed by the deity lending only their authorial voice to the literally word-for-word transcript given to them by God. (For support they quote scripture, of course, "All Scripture is God-breathed and useful for teaching, rebuking, correcting, and training in righteousness" (II Timothy 3:16). Believing that, the stakes become incredibly high for a biblical literalist, many/most of whom are also YEC. If any scripture is found to be "false" by modern standards, it basically invalidates the whole thing.
I say this having believed this version of Biblical inspiration and knowing I'd have been given permission to teach it in church once upon a time.
The tricky bit is that modern standards aren't an appropriate measure to hold an ancient document with different goals, but that's literally a books worth of argument and background to dive into.
Regardless I think the comment was about applying current "solutions" to prior times and seeing if agrees with what we'd call a good solution in retrospective, not what people believe currently.
My older brother has founded two separate isotope dating companies, one for C-14 dating and the other for rare isotopes. At this point, he has about 15 years of experience in the field and a decent clientele.
He believes the Earth is 6000 years old, though. He rationalizes the science he works on as (the biblical) God testing his faith. My father, who works at his C-14 company, also believes this. I will never understand.
Honestly, if God created the universe 6,000 years ago and made everything seem as if it were older—I mean, that’s just a fundamentally unfalsifiable metaphysical hypothesis. For all we know, God did that last week or maybe 5 seconds ago. There’s nothing stopping that hypothesis from being true, it just makes, by definition, no measurable or practical difference and is hence irrelevant to scientific inquiry.
But that would go against how things are supposed to work according to the Bible: would God really be playing a big trick, aiming to deceive? A philosophically motivated abstract godlike being might be expected do that, but the Bible is a lot more specific than that about what God's like...
I mean, to account for the existence of stars over 6k light years away you basically have to embrace the "God is fucking with us" view anyway. It's the _only_ context in which YEC could work.
I was just arguing a distinction between physical and metaphysical truth. My “theology”, such that it exists, is merely that God is fundamentally beyond human understanding and that we can’t meaningfully use human motivations or morality to model God’s actions.
If everything about God is beyond human understanding, then a belief in that god doesn't leave you with any more beliefs than you started with, which makes it atheism by a different name. I would argue that you would have to have at least one religious belief to be counted as religious (and no, "the belief that I have a religious belief" doesn't count.)
Probably not the right venue for a deep theological discussion, but ya, don't you give the right answers in tests? Like if it was a test of faith about God's existence in an atheist society, the right thing to do would be to proclaim "God exists". But here, the test is to pretend that the lie is true to everyone else, but in your head, to know that this isn't the right answer?
In this moral framework, I wonder what the right ethical thing to do when another creationist is the customer? Do they both accept the lie^H^H^Htest of faith?
It's a test of personal faith, they don't have to proclaim it to others to 'pass the test'. They pass the test by having faith without proof.
It depends on how they interpret the results to the customer. They might show the data and say that "it seems that this rock is million years old". They don't have to believe it themselves.
If the customer is another creationist, they probably marvel the perfection of God's creation and how impeccably he has been able to fake the age of the universe. You know, they probably see it as an evidence of God's omnipotence.
I can only initially rationalise that as "start from God and work back" and "start from science and work forwards".
Whether you ever get to the bottom of this, keep loving them both. That is something that does not need a god or science or even a capital letter - I'll assert: Love is the fundamental thing that transcends any ideology.
I have some pretty odd ideas myself and I trained as a Civ Engr, run an IT company and have subscribed to New Scientist for about 30 years.
Sometimes I notice aspects of my own woolly thinking and sort them out but I've no doubt that many remain. The funny thing is that "woolly" is in the eye of the beholder or something.
I'm not daft enough to have misplaced 85% of the entire universe unlike the entirety of physicists and their "science" 8)
Some people do now (particularly in the US; while some form of creationism is somewhat common worldwide, literalist young earth creationism is mostly a big deal in some US protestant religions). But it's a fairly new invention as a semi-mainstream concept. It emerged in the 20th century.
I've heard the argument that God did create everything about 6,000 years ago in HIS reference frame but that due to relativistic time dilation/contraction its been 13+ billion years in OUR reference frame.
I think the implication was at the time this article was written that was a common belief. Therefore, the possibility that something was millions - or hundreds of millions - of years old would have been against the current orthodoxy and therefore would have been banned.
That's not really correct, though. Young Earth Creationism as a dogmatic point is a 20th centry invention; while people may have kind of assumed the world was pretty new in the 19th century it wasn't really orthodoxy.
How do you know they are not the general population? I honestly have no idea what anyone else believes in that regard. Even if someone told me what they believe, I’ve learned that often people’s beliefs are different than the words they say when they think their beliefs might be unpopular. In other words, maybe they are the general populations beliefs and maybe they aren’t. I just don’t know how anyone can know for sure.
I'm going by anecdote to denote the general population's opinion, ie what people have said to me.
I do agree with you that people attenuate their espoused beliefs based on perceived popularity and that is why I put the comment in [] above. Sometimes I think we need to affirm our own beliefs sometimes and that is what I've done by asking for dialogue and not downvotes.
I'm talking about 1863, and referring to discussion happened yesterday, about videos removed from Youtube due to being not supported by currently prevailing scientific views and opinions . Apologies for not being as clear as I want myself to be )
I'm pretty sure then, as now, the readership of SA was not reflective of the population as a whole! I'm pretty sure you could find all kinds of bizarre conspiracies from this era as well. (e.g. all Catholics are trying to take over the United States for the Pope)
One of my favorite sections of SA back when I read the dead tree version is they would have a page near the front of the journal that highlighted what was the top news in the issues 50, 100 & 150 years prior.
No, it isn't. It's correct in the basic claim of the title. Scientists in 1863 who believed that no known source of energy was capable of powering the Sun were right. The Sun is not powered by any source of energy that was known in 1863.
> I would prefer if there was some more working shown to back up the article
Scientific American wasn't the place to show the details then any more than it is today. But the calculations are simple to do, and plenty of physicists had done them at the time of the article.
A summary of the calculations:
Chemical reactions, which is what burning coal is an example of, produce an energy per unit mass of fuel on the order of 10^8 Joules per kilogram. (That's actually on the high end, but it's fine for a rough calculation.) The Sun's mass is about 2 x 10^30 kilograms today; if we assume that half of that is burned as fuel, we get a total energy of 10^38 Joules. The Sun's power output is about 4 x 10^26 Watts, so 10^38 Joules will supply the Sun's power output for about 2 x 10^11 seconds, which is pretty close to 5,000 years (a year is about 3 x 10^7 seconds).
Meteorite impacts essentially convert gravitational potential energy to heat, so the energy per unit mass available is the change in gravitational potential energy from the average distance of a meteorite from the Sun when it starts falling in, to the radius of the Sun. That difference is GM/R - GM/r, where R is the Sun's radius and r is the distance from which the meteorite starts falling in. If we take the maximum possible change, that will be for r -> infinity, in which case our potential energy gain is just GM/R. G is about 7 x 10^-11, M we have from above, and R is about 7 x 10^8 meters. This works out to 2 x 10^11 Joules per kilogram. At that rate, to supply the Sun's power output for 100 million years (about 3 x 10^15 seconds) would take about 6 x 10^30 kilograms, or 3 times the Sun's mass.
That tells me that the article greatly overestimated the potential mass of meteorites available, since the Sun is something like 99 percent of the mass of the solar system, and even counting in the Oort cloud doesn't change that number appreciably. An optimistic upper limit based on current knowledge would be something like 0.1 percent of the Sun's mass (since most of the 1 percent of mass that is not the Sun is the planets, not meteorites), and even that is probably much too large. But taking that value gives an time of 1e12 seconds, or about 30,000 years.
(Note that later in the 1800s, someone--I think it was Lord Kelvin--calculated how long the Sun could be kept shining by gravitational contraction--i.e, by just contracting its own mass to a smaller radius and converting gravitational potential energy into radiation. He came up with a figure of something like 10 million years, which is about what you get if you take the potential energy change formula I gave above and plug in an r--the distance from which "falling in" starts--of something like twice the Sun's radius, and then multiply by the entire mass of the Sun. That's basically what Kelvin's calculation did.)
The article is using meteorites as an analogy; the model is of the Sun forming by gravitational contraction of a gas cloud, for which an r of infinity is appropriate.
What's interesting is that the power available from solar fusion is of a similar order of magnitude to that available from gravitational contraction. But of course it must be, because if fusion was too powerful medium-mass stars wouldn't be able to form to provide light and heat to habitable worlds, and if it was too weak then giant stars wouldn't be able to overcome their gravitational binding energy in supernovae to disperse the elements that form habitable worlds.
> What's interesting is that the power available from solar fusion is of a similar order of magnitude to that available from gravitational contraction.
No, it isn't; fusion provides much more energy per unit mass than gravitational contraction would for the Sun. As I calculated, gravitational contraction falling in from infinity to the current radius of the Sun provides about 2 x 10^11 Joules per kilogram. Fusion provides about 5 x 10^14 Joules per kilogram (the exact number depends on the particular fusion reaction).
> Assuming that the heat of the sun has been kept up by meteoric bodies falling into it, it is possible from the mass of the solar system to determine approximately the period during which the sun has shone. The limits lie between 100 millions and 400 millions of years.
I don't know how the mass of the solar system figures in their calculation, but you can say that the total mass of meteorites so far must be less than the current mass of the sun.
The energy of a meteorite falling into the sun should be about 1/2 its escape velocity squared.
>>> sun_escape_vel = 617.5e3 # m/s
>>> sun_infall_energy = 0.5 * sun_escape_vel**2 * sun_mass # kg m/s^2 or J
>>> sun_infall_energy / sun_output / year
31586055.04077674
(This is a loose upper bound, because I'm assuming the same escape velocity the whole time but the sun would have started at lower mass.)
So mass falling into the sun could sustain its output for 31 million years.
In fact when Cecilia Payne proposed that the Sun and other stars were composed of Hydrogen and Helium in her Doctoral thesis in 1925 the conclusion was rejected by her advisor because of the conventional wisdom of the time that the earth and the sun were composed of the same elements. https://en.m.wikipedia.org/wiki/Cecilia_Payne-Gaposchkin
I thought helium was named for the sun (Helios), by spectral analysis of sunlight. In hindsight it's weird that they can know that in the 19th century (per Wikipedia of Helium) and the next conclusion has to wait until 1925, with controversy.
They probably thought it was an inert atmosphere found on the Sun but having nothing to do with the operation of the Sun. Without nuclear physics, it wouldn't be an unreasonable conclusion.
And the helium that can be "seen" on the Sun is not due to fusion IN the Sun, but rather is from the gas cloud from which the Sun formed. The solar core and the surface are not connected by convection.
Not, if you know that there was simply not even a concept of nuclear fusion in 19th century, and that the year of discovery of electron is 1897, and of the existence of atomic nucleus 1909.
Tangentially, but also interesting and illuminating how non-trivial all that was at that times, neutron was discovered as late as 1932 -- the same year that Hitler became chancellor of Germany. It is that recent, and it was that hard.
This slots into the wider story about how science found out about the age of the earth, which is fascinating!
In the 1860s Lord Kelvin presented[1] one of the first physical arguments in favor of the earth being millions of years old. His argument was that we could predict the age of the earth by measuring the temperature gradient at the surface of the planet (which is related to the amount of heat that is being radiated to space). He modeled the earth as a cooling solid sphere and using the heat equation[2] he computed that if the earth started at the temperature of molten rock then it would take some tens of millions of years to cool down to the current surface temperatures. Conveniently, this estimate matched contemporaneous theories about the sun being powered by gravity. If one assumed that the sun was slowly shrinking while releasing that gravitational potential energy as light, it also ended up with an age of some tens of millions of years. (Remember: back then neither radioactive decay nor nuclear fusion had been discovered yet).
The major flaw in Lord Kelvin's calculations were only discovered in the 1890's when Irish mathematician John Perry suggested that modelling the earth as a cooling solid sphere would not be appropriate if the earth's core were actually liquid. The key difference is that a liquid core transfers heat much more efficiently, due to convection. In the presence of a liquid core the surface of the earth receives more heat from the interior and takes longer to cool down to the present temperatures, compared with an earth that has a solid core. Once Perry corrected Kelvin's model to account for convection the age of the earth jumped to the billions of years that we now know it has.
It took a while for the theory of the convective mantle to become widely accepted but it was ultimately proven correct by radiometric dating.
The key is not the liquid core, but the convective mantle. The mantle is solid, but still convects by plastic deformation. It was this ignoring of solid deformation that got Kelvin in trouble. He reasoned that since the mantle transmits shear waves, it cannot be liquid, and (hence, incorrectly) cannot convect. This despite clear evidence from geology that hot rocks under strain can become highly deformed.
This is really interesting, because we had a lot of the machinery in place to make accurate observations, but not a lot of the theory to link them together. We've known about sunspots since the Han dynasty and had accurate measurements of its size, distance, and temperature since the mid-1800s when spectroscopy became available.
But it took Einstein himself and the legendary E=MC^2 equation to demonstrate a theoretical source of energy that powers the sun, well into the 20th century.
"In 1920, Arthur Eddington suggested hydrogen-helium fusion could be the primary source of stellar energy. ... laboratory fusion of hydrogen isotopes was accomplished by Mark Oliphant in 1932. ... the theory of the main cycle of nuclear fusion in stars was worked out by Hans Bethe." https://en.wikipedia.org/wiki/Nuclear_fusion
Right, I wasn't saying he did. I was trying to say that, without a theoretical framework to hang that kind of energy generation on, there was no capacity to understand what was going on. E=MC^2 is precisely that kind of theoretical framework. Pretty amazing, to me. Being able to say "It's this far away, this hot, and this large, but why?"
I don't think thats true though. In 1903, Radioactivity had already been proposed as an explanation for the Sun's heat (2 years prior to Annus Mirabilis). The connection between E=mc^2 and nuclear reactions doesn't become clear until you start losing mass (proton + neutron) in the reactions, which doesn't happen for the reactions involved in the Sun (Carbon Nitrogen Oxygen Cycle). The connection was recognized by Lise Meitner and Otto Hahn when they discovered fission, where a mass loss does occur. However, they didn't publish their discovery until January 1939; and Hans Bethe had already been working on the Carbon Nitrogen Oxygen Cycle, and didn't need fission to account for the Sun's processes (neutron + proton mass is conserved in the relevant reactions). He was just working off of observed empirical data to make his conclusions.
E=mc^2 is a consequence from special relativity, not a theoretical framework. It also has very little to do with the understand of nuclear reactions. The reason why nuclear reactions release much more energy than chemical reactions is that the binding energies inside the nucleus are much larger than inside the electron shell. Mass-energy equivalence exists in both cases.
Indeed. And in a Newtonian universe, it's possible that something like nuclear fusion could exist that would liberate much more than mc^2. There would be no upper limit on nuclear reaction energies set by the total rest energy of the reactants.
It was definitely a conundrum for scientists. Throughout the 19th century, evidence kept piling up from geology supporting longer and longer time periods for the age of the earth, but there was no known source of energy that could keep the sun burning for that much time.
To be fair, the cosmological constant is a fair stab at a guess for dark energy. Like, space has an intrinsic property N that's allowed in the equations. That's a decently shaped guess.
> Luminiferous aether or ether[1] ("luminiferous", meaning "light-bearing") was the postulated medium for the propagation of light.[2] It was invoked to explain the ability of the apparently wave-based light to propagate through empty space, something that waves should not be able to do. The assumption of a spatial plenum of luminiferous aether, rather than a spatial vacuum, provided the theoretical medium that was required by wave theories of light.
> The aether hypothesis was the topic of considerable debate throughout its history, as it required the existence of an invisible and infinite material with no interaction with physical objects.
It wasn't that far-fetched as it sounds now: using Maxwell's equation, one can easily derive the speed of light, c. But then the question is: speed relative to what? Because Maxwell's equation doesn't tell exactly what it is relative to.
But, as we all know, speed is relative, so it must be relative to something - then the something ought to be the medium for light. So people started looking for it - and it refused to show up even when it should! The famous Michelson–Morley experiment.
Of course, it was resolved by theory of relativity: it turns out the speed of light is relative to everything! You just have to slow down time itself, no big deal.
I always found this fascinating. The enormous shift in physics that occurred in the early 20th century must have been so exciting to experience first hand.
It seems like it had a lasting psychological impact on the thinking of the generation of scientists, who lived through this radical revolution .
I found very interesting this moment in an interview with Freeman Dyson, where he describes the difference in thinking between two generations of scientists around 1950 (Oppenheimer, Bohr, Heisenberg… vs. Feynman, Schwinger…):
"they lived through this radical revolution of quantum electrodynamics, which was so successful, they wanted to have something like that again"
"each of them had radical proposals, which turned out to be totally useless and in the meantime it was the young people who actually were the conservatives"
My favourite factoid about the aether theory is that Faraday found it implausible, on the basis that he couldn't conceive of a fluid medium that could propagate transverse waves evenly in all directions, but not longitudinal waves in any direction.
My favorite is the erroneous theory of immunization that informed Pasteur's successful development of a vaccine:
Accordingly, why was Pasteur such a genius as to discern how the immune system functions to protect us against invasion by the microbial world when no one had even made the distinction between fungi, bacteria, or viruses, and no one had formulated any theories of immunity. A careful reading of Pasteur’s presentations to the Academy of Sciences reveals that Pasteur was entirely mistaken as to how immunity occurs, in that he reasoned, as a good microbiologist would, that appropriately attenuated microbes would deplete the host of vital trace nutrients absolutely required for their viability and growth, and not an active response on the part of the host. Even so, he focused attention on immunity, preparing the ground for others who followed.
I think it is. Electric and magnetic fields exist in relationship with the processes that create and shape them. There is no prerequisite "background electromagnetic field" that is universally necessary for all of those processes, to begin with.
The primary difference is that the aether was supposed to provide a universal rest frame, which we now know doesn’t exist, but quantum field theory does posit that the field is a fundamental medium and the particles exist only as perturbations in that field.
Not only that, cosmic plasma filaments carrying charged dust around is the most likely explanation for the "missing" matter and energy that two Nobels were handed out for the, continued, non-discovery.
I do not understand why the Aether was ridiculed, but Dark (Matter|Energy) are not. They both depend on something we can't see or detect in any way, and Occam's Razor dictates that, without further evidence, I have to consider the least complex explanation the probably correct one: Plasma physics is a well understood field that involves the Electromagnetic force, and Cosmology has simply neglected to understand how large plasma currents can scale to.
The irony is, Hannes Alfvén (1970 Nobel Prize winner for his work on Magnetohydrodynamics, also had significant contributions to space science) basically stated that this is the most likely cause of coronal heating, based on the earlier work of Kristian Birkeland (nominated for the Nobel 7 times)... gigantic plasma currents slamming into the Sun at it's polar regions, much like how the Solar magnetic field slams into us at our poles and causes high energy plasma events known as the Aurora.
It's wrong to ridicule aether. It was a theory, the theory was tested, and it turned out to be wrong. Lots of theories are wrong. It's not like scientists at the time were stupid. James Clerk Maxwell believed that an aether was required, and he was literally the first person to write down the full set of equations for electromagnetism. Occam's razor doesn't tell us that aether is less parsimonious than "Literally, time slows down when you go faster. Also, light is a particle and a wave at the same time. Kind of."
Aether suffered from clear problems as an idea as the long list of weird properties it had to satisfy, and the list only got longer and longer. Dark matter isn't like that at all -- it's easy to add to our theories that there's a particle that is invisible but has mass. There's no Michaelson-Morley experiment that's extremely hard to explain.
That passage really brings into perspective how old Scientific American is, or maybe how little ago it must've been that the composition of the sun was discovered. This was during the American Civil War.
He's incorrect in that the Standard Model firmed up in the 1970s. But since then, fundamental physics has been nearly stagnant.
More broadly, the era of exponentially growing knowledge of the basic foundations of the universe cannot last long. Historically it will be seen as highly anomalous. Most of history will be one of scientific stagnation.
Any exponential growth process runs into fundamental limits soon enough. This is as true in physics as it is in any other field. Accelerators are close to their practical limits, for example.
Apparently it was Darwin developing his theory of evolution, who first realized that the Earth and thus the Sun must be much older than a chemical burning process would support. That left him very puzzled since there was no physics theory that could support that.
Although Charles Lyell had already suggested the Earth was much older than 6000 years in Principles of Geology in 1830. Darwin took the first volume of Lyell's book with him on the Beagle.
When I was a child, my father had a 'Scientific American' monthly magazine subscription for our household.
I always got a kick out of the regular features, "50 years ago" and "100 years ago", where they excerpted their own actual articles from exactly that long ago. Definitely gave me a sense of perspective on the march of scientific understanding.
(By 1995, they were able to add "150 years ago", as they'd been in existence since 1845.)
To me, I think what this demonstrates more than anything else is that the human mind is limited by the metaphors it has access to.
Leaving astronomy out of it— just look at the how we describe the mind — it’s been variously described as breath, or hydraulics, or clockworks and now as a computer.
Probably in 100 years we’ll be looking back at our primitive understanding of how the brain works and laughing.
They thought the sun might be made of coal because they were excited by the industrial revolution and the discover of thermodynamics and the steam engine and thought it might be the same phenomenon.
I don't think it is a matter of metaphors at all, but simply a limited understanding of laws and forces. There wasn't a force known at the time that could produce so much light and heat for so long with the mass of the sun. The only conceivable way to produce light and heat like that was to burn vast quantities of fuels.
I added it. In a way it's dodgy though, because SA isn't providing the original article or even a photo of it. This is just a single-paragraph quote, and they've milked that cow before: https://www.reddit.com/r/askscience/comments/1jym5d/in_the_s..., which I ran across while failing to track down the original article.
When I worked for The Atlantic, I learned that Django/MySQL was not made to work for dates in the 1850s... I forget what the exact nature of the bug was, but you had to be careful which date class you were using because some can’t go past 1900.
Articles like this, are a good reminder, to maybe not be tooo hard with the anti-science crowd. Or the ignorant about science crowd.
It is all quite new, and probably take some more years, to sink in. So keep that in mind, the next time you discuss with anti-vaccers, anti climate change, ... as that level of ignorance can get depressing otherwise.
There's a HUUUUGE difference between "We have all this data and no theory to explain it all" that we had for the sun for a long time, and "I read something on twitter once that matches with an anecdote from uncle Buck that means vaccines cause autism"
A decent amount of our stuff. It’s important to read stuff like this to encourage a little humility. These guys were no less smart than we are.
When you read stuff like this from an earlier era it’s always shocking just how different their frame of reference is, what’s considered important and what’s assumed common knowledge. The book “But What if We’re Wrong?” By Chuck Klosterman really does a great job looking at this question.
I'll check that out. I read somewhere that there's a bias where we all believe we are living somehow at the end of history, and that surly this time we have everything right.
Backing up your point about smartness not being the problem, there's a quote, I think from Lord Kelvin of 'the kelvin' fame, saying something like all science has basically been discovered and we just need to fill in the details. We just can't help believing we are at a somehow special point in history.
I was once at a tech conference for high schoolers in London where one of the distinguished speakers (others included Vint Cerf, and a UK government minister) told us that the primary reason the sun is hot was because it was still glowing with heat from the pressure of gravitational collapse.
I think their claim was that the nuclear reactions in the sun contributed to the Sun’s radiation, but did not contribute to the bulk of the Sun’s temperature (heat?)
I’m a little fuzzy, but I’ve never seen this claim elsewhere. Is it true?
A star like Sun is in a state of an equilibrium between gravitational forces that want to collapse the star and the fusion energy. Gravitational pressure helps atoms to collide and fusion takes place. But it doesn't sound right to say that the heat is from the pressure.
Once the fusion energy isn't enough to counteract the gravity, the star collapses into a white dwarf (or a super-nova later).
I hope they are able to figure this out, I would be interested to know how long the sun could burn on oil or kerosene. /s
Legitimately though, assuming the sun is fake, how would one build an artificial sun? What could reasonably power it and give the impression to a planet within that it is real? Perhaps the problem could be even tougher if you're also trying to replicate the mass.
The plot could be some advanced civilization planning to steal a near-by star and replace it with a fake, possibly to build a Dyson sphere around it to cypher off the energy. Could you fool the less-advanced civilization into thinking they still have a real star? (Ignoring the logistics of the actual swap.)
A proposal for radiation: You could burn lots of fuel and radiate tonnes of energy out into space, but if you're only trying to fool a few planets, perhaps you could direct energy at them. I'm not entirely sure what you would have to do in order to make the light arrays appear correctly though.
A proposal for mass: It seems as though a sustainable black hole could at least be as small as 3.8 times the mass of our sun [1] and a valid star could be > 1000 times the mass of our sun [2]. There's more than enough wiggle room there that you could have a small black hole within an outer shell, so the orbits could continue as normal.
Possible problem with pointing lights at planets is that eventually they'll notice the moving beams from the faint zodiacal light. Of course they won't immediately conclude "the sun is a giant planetarium projector" but it will likely spur greater curiosity in observing the sun from different viewpoints.
If you have a small black hole, you'd rather build a dyson sphere around that. They're pretty good matter-to-energy converters: https://arxiv.org/abs/0908.1803
This is precious lol! The 6000 year old earth theory would be a lot less arbitrary in this light, for that time period. I can see how that theory would become relegated to vestigial religious groups.
Interesting that Sun burning coal age is well under billion years, while white dwarfs - which don't have corresponding reactions supporting the light emission - can live a trillion years.
I would really like to be in 150 years in the future to see what assumptions we are making today are totally foolish like that was the case is sun as coal ;)
It’s pretty much guaranteed that we currently have a lot of beliefs that will look completely ridiculous in a few hundred years. I am also curious which ones...
It's curious how in less than two hundred years our world-view has changed so drastically. Of course, scientific advances compound. But so do ways of thinking. Anybody who is lucky enough to get the word "Almighty" in a Science paper these days is just cracking a very good joke that made it through a lot of reviewers. But less than two hundred years ago people still felt they had to acknowledge His existence in words while undoing Him in facts.
No, such Bible-based estimates are far older. I found a review that seems comprehensive, albeit reaching an incomprehensible (to me, anyway) conclusion.[0]
To clarify, the modern young Earth creationism that formed as an alternative to scientific consensus. We've had strong evidence that the Earth is very, very old for hundreds of years, which was the scientific and religiously backed conclusion in the early 1800s. At the time this article was written, it would have been well understood and accepted, with no religiously driven explanation counter to scientific evidence. Any explanation put forth for an old or young Earth prior to scientific evidence for it is just blind guessing by philosophers.
> We've had strong evidence that the Earth is very, very old for hundreds of years, which was the scientific and religiously backed conclusion in the early 1800s.
Sure, among experts. But what about popular opinion? And did the Scopes trial (1925) mark a resurgence in creationism?
Not particularly, in my opinion. Look at any group derided, not by the scientific community, but by the laymen who accept scientific consensus; Antivaxers, climate change deniers, YECs. They raise one or two, often valid, objections to the current state of affairs and rather than getting a reasonable, coherent explanation for why it's the scientific consensus, they're mocked, again, by laymen who really couldn't answer their questions anyway. They questioned the divinity of popular science, and as heretics, deserve to be burned. People are reasonable and logical by default. We form our beliefs from knowledge and experience, and these groups are no exception.
"Age of the Sun -- Force and Heat"
Scientific American Vol IX -- No. 7
August 15 1863
https://babel.hathitrust.org/cgi/pt?id=uva.x001601382&view=1...