Yes! He answers why the sky isn't violet, love it!
Why is the sky blue?
171–180 of 279 posts
Re: Why is the sky blue?
#172Earlier quoted context omitted.
It also needs a bit of biology. Our eyes don't have a flat response over frequency, they're more sensitive to blue than violet. Violet gets scattered even more than blue, and the violet light does shift our perception of the color. But it does so less than it would if we had photoreceptors more sensitive to violet , so the resulting perceptual color depends not just on the intensity of the light at different frequenc…
There are differences in receptor behavior across species, but they are understandably clustered around the parts of the spectrum in which sol is most luminous. An earth-like planet orbiting a different star would likely have evolved photoreceptor arrangements which match that star instead. So after scratching the biology itch we'll probably need to talk about fusion byproducts in sol-like stars.
> they are understandably clustered around the parts of the spectrum in which sol [sun] is most luminous
That would be understandable but it’s not what’s going on: http://hyperphysics.phy-astr.gsu.edu/hbase/Chemical/watabs.h...
Re: Why is the sky blue?
#173Obligatory xkcd: "Sky Color" https://m.xkcd.com/1145/ Obligatory xkcd[2]: "Rayleigh Scattering" https://m.xkcd.com/1818/ Others?
Surprisingly, neither TFA or anyone in the comments linked to a photo of liquid oxygen. It's very obviously blue.
The liquid air article on wikipedia doesn't have any photos.
Re: Why is the sky blue?
#174Earlier quoted context omitted.
The "Rayleigh Scattering" comic is really spot on. Air is blue. The reason air is blue is blah blah blah physics, see the article we're all commenting on, but at the end of the day air is blue. We don't demand the same elaborate physics questions for why a ripe banana peel is yellow.
Though is some cases it is a very interesting question, like why gold and copper the color they are instead of being boring and silvery like all the other metals?
The transition metals are colourful because their outer shell of electrons (d-block) are about visible-light sized.
Looking at a periodic table makes this pattern kinda clear.
Re: Why is the sky blue?
#175Earlier quoted context omitted.
I am positively excited about the upcoming first generation of humans who will have all their questions answered, correctly and in the way they can best understand, and as often and many of them as they want – and what that is going to enable.
The same anticipation of great things happening preceded the arrival of widely available internet, but all we really got was cat videos initially, and doomscrolling more recently. I don’t have much hope for great things anymore.
I just did a crash course on lingustics by reading through a bunch of highly specialized articles.
30 years ago, just finding those articles would require spending many hours in the library (and that's if I'm lucky and the library has them).
It's definitely not just cat videos.
Re: Why is the sky blue?
#176Earlier quoted context omitted.
Now do clam steamers and shrimp fried rice.
I'm familiar with "steamer clams", but not "clam steamers". In "shrimp fried rice", "shrimp" is a noun adjunct [1], which is when you use a noun as an adjective. The charming ambiguity comes from it being unclear whether "shrimp" is an adjunct noun modifying "fried rice" ("shrimp fried-rice") or modifying the past participle verb "fried" ("shrimp-fried rice"). [1] https://en.wikipedia.org/wiki/Noun_adjunct [2] https:…
I thought the charming ambiguity came from "fried" either acting as an adjective or as a verb. These aren't just any shrimp, they're chef shrimp, and they've prepared some delicious fried rice for us. Isn't that incredible? Shrimp fried rice.
Re: Why is the sky blue?
#177In The Cuckoo's Egg Cliff Stoll recounts an episode from the oral defense of his astrophysics PhD thesis. A bunch of people ask questions but one prof holds back until... """ “I’ve got just one question, Cliff,” he says, carving his way through the Eberhard-Faber. “Why is the sky blue?” My mind is absolutely, profoundly blank. I have no idea. I look out the window at the sky with the primitive, uncomprehending wonder…
"Could you be more specific" is a great question to find out more what the person knows and how they thing. You give an answer that, just due to the nature of knowledge and the limitation of language, has some black boxes. And "could you be more specific" is basically asking to go through the black boxes. Its like asking how does Java work or something like that? You can go from "The JVM interprets java byte code" to…
Having two older brothers who are famous trial lawyers, I can attest that it's both an effective line of questioning and a deeply infuriating one. What I learned is that up to a certain point, it's feigned ignorance probing whether one knows a principle behind a stated principle. Beyond that point, though, you can basically make shit up and they won't know the difference. Come to think of it, this is also the sleight-of-hand pulled by LLMs when you ask them for more and more detailed answers. The trick is knowing when your interrogator no longer knows the answer.
[edit] Also, in my family, you'd ask Dad these questions. And if he didn't know the answer, he'd pull out the Britannica, and have you look it up, then go over it with you until he understood it well enough to explain it. "No short answers" was his motto. (He was also a trial lawyer). Most people are just not equipped to handle cross-examination, and it's scary for them... but the primary reason is that they never learned to admit when they don't know the answer.to a question, and that admitting you don't know is not a failing, but actually a strength, especially if it impels your curiosity to go find the answer.
Re: Why is the sky blue?
#178One technical point about resonance: the fourth-power law only applies when the driving frequency (i.e., the frequency of visible light) is far below the resonant frequency (which is in the UV region of the spectrum). The approximation breaks down the closer you get to the resonant frequency and also above.
I was confused about how a monotonic function (f^4) could possibly describe a resonance phenomenon (which ought to have a strong local extremum), and this is the answer.
Re: Why is the sky blue?
#179I have a related but deeper question about sun and colors: Sunlight in space is considered white. When it reaches earth surface, it's considered a warmer color. Why human eyes that never (during evolution) saw sunlight without the atmosphere, consider it true white, and not colder color?
In space, there is only direct sunlight. On Earth, you have to consider illumination from the whole sky.
On Earth, the sun's disc at noon appears yellow-ish due to being white minus some blue light scattered away by the atmosphere. But there is also the rest of the sky illuminating the ground, as you can still easily see in shadowed areas. That is blue light from the sky hemisphere.
It very approximately adds back up to white overall for something exposed to direct sun and the whole sky, depending on the sun's position in the sky.
Re: Why is the sky blue?
#180This was both very informative, easy to understand, and fun to read! That's a winning combo. I now know a bit more about why the sky is the color it is. Thank you for making it. :) (The blog post, that is, not the sky. If you made the sky - please let me know!)
Thoroughly enjoyed reading this too! Kudos and shout out to the author Erik Kennedy. One can definitely see the care and love. We hope to see more of this style the future
Kind of reminds me of worrydream (Brett Victor), better explained and neil.fun vibes (and many others I can’t recall right now)