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Experts Doubt the Sun Is Burning Coal (1863)

scientificamerican.com

111–120 of 244 posts

Re: Experts Doubt the Sun Is Burning Coal (1863)

#111

Earlier quoted context omitted.

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.

Sounds a little like Dark Matter and Dark Energy today. Lots of evidence for it but nobody knows what it is.

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.

Re: Experts Doubt the Sun Is Burning Coal (1863)

#112
post #64

Earlier quoted context omitted.

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 jus…

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.

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.

Re: Experts Doubt the Sun Is Burning Coal (1863)

#113
post #94
post #22

Earlier quoted context omitted.

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.

Perhaps use the link posted by: https://news.ycombinator.com/item?id=23075544 instead.

Thanks! That's maybe not readable enough to be the primary URL but I've pinned that comment to the top.

Re: Experts Doubt the Sun Is Burning Coal (1863)

#114
post #15

I had absolutely no idea that SA is so old. New Scientist - https://en.wikipedia.org/wiki/New_Scientist is a mere whippersnapper. 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…

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 jus…

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

Re: Experts Doubt the Sun Is Burning Coal (1863)

#115

Earlier quoted context omitted.

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 unders…

How do they reconcile when they give customers answers > 6000 years and the whole "thou shalt not lie" bit?

Maybe this: https://en.wikipedia.org/wiki/Omphalos_hypothesis

Re: Experts Doubt the Sun Is Burning Coal (1863)

#116
post #109

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 ci…

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

Re: Experts Doubt the Sun Is Burning Coal (1863)

#117

Earlier quoted context omitted.

> (Also, it’s “oblate”. To “ablate” is to erode.) Perhaps, but the item "ablate" in "an ablate spheroid" is obviously not a verb, so it's hard to see how that's relevant. "Ablate" isn't really well-formed for a verb, and indeed I see that the modern verb is a back-formation from the better-formed "ablation". If it had started as a verb, you'd expect "aufer", in the same way that we have the verb "offer" rather than "…

Talk about doubling down with nonsense when you've patently spelled it the wrong way. SMH.

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.

Re: Experts Doubt the Sun Is Burning Coal (1863)

#118

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 theoretic…

Einstein did not determine that the sun was nuclear powered. That was Hans Bethe in 1939 (based on data produced by Bengt Strömgren).

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?"

Re: Experts Doubt the Sun Is Burning Coal (1863)

#119
post #80

Earlier quoted context omitted.

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 bet…

> I was deliberately provocative and I'm glad I was. I've got far better responses as a result. I would tend to argue that this isn’t something we need on Hacker News. (Also, it’s “oblate”. To “ablate” is to erode.)

> To "ablate" is to erode.

I mean, it's a ablate sphereoid too, thanks to rainfall, but that's clearly not what they meant.

Re: Experts Doubt the Sun Is Burning Coal (1863)

#120
post #69

Earlier quoted context omitted.

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…

"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.

0) https://en.wikipedia.org/wiki/Arthur_Eddington

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