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Why is the sky blue?

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Re: Why is the sky blue?

#181

Post by codesnik »

reactordev wrote: post #166
jaggederest wrote: post #163

Earlier quoted context omitted.

We already have mutations, generally in women, for tetrachromaticism, who usually have male relatives with severe or moderate color blindness, in which the X chromosome encodes a different green cone. So they end up seeing red, strange-green, green, and blue, where strange-green is somewhere closer to red than green. Only a few on record but they tend to have absolutely insane color matching and color perception. One…

I have that already ;) it actually looks like muddy puke green than green. However, green stop lights look more “white” than green. Some reds look like brown. I hate reds. I’m not sure about the Pantone-like color matching but I definitely see different colors than most people. To the point where my flight license is restricted. Dichromatic but not trichromatic.

how does dichromatism restricts flight license? no instrumental flights? no night flights? something about perceiving warning lights on some panels?

Re: Why is the sky blue?

#182

Post by yawpitch »

jxdxbx wrote: post #129
yawpitch wrote: post #77

The sky isn’t blue. It’s transparent. That’s why you can see stars that aren’t blue at night. When struck by sunlight at the right angles it appears blue, but saying it is blue is like saying the ocean is green when a bucket of it clearly isn’t.

If something appears blue, it is blue. That’s all color is. Also, if you took a sufficiently large quantity of air and put it into empty space and shined very bright white through it, it would experience rayleigh scattering—-meaning that air, when you have enough of it and shine a bright enough light through it, is blue.

By that logic the sky is near-Planck length ultraviolet, because if I put a sufficiently large quantity of it immediately beside a supernova it goes way past blue.

Color is a property something has under certain conditions, it is not a property of what that something is under all conditions.

Re: Why is the sky blue?

#183

Post by yawpitch »

mncharity wrote: post #140
yawpitch wrote: post #77

The sky isn’t blue. It’s transparent. That’s why you can see stars that aren’t blue at night. When struck by sunlight at the right angles it appears blue, but saying it is blue is like saying the ocean is green when a bucket of it clearly isn’t.

Perhaps "transparent with a blue tint"?

I’ll allow “transparent with an occasional blue tint under the current conditions of its nearest star”.

Re: Why is the sky blue?

#186

Post by hgomersall »

gh5000 wrote: post #108
margalabargala wrote: post #12

Earlier 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.

But a banana is yellow for a very different reason (and a much easier to explain reason) than why the sky is blue. And air isn’t blue, because it’s red at the end of the day?

Why is a banana yellow?

Re: Why is the sky blue?

#187

Post by mzhaase »

thoughtlede wrote: post #103

I think we can simplify the answer to this question for most audience and say "the air is blue". If they say, the air appears to be clear when I stare at something other than sky, the answer is you need more of air to be able to see its blue-ness, in much the same way that a small amount of murky water in your palm appears clear, but a lot of it does not. If they ask, why don't I see that blue-ness at dawn or dusk, t…

Liquid oxygen has the same color.

Re: Why is the sky blue?

#188

Post by orlp »

munificent wrote: post #41

Really cool article! Tangential: > “Scattering” is the scientific term of art for molecules deflecting photons. Linguistically, it’s used somewhat inconsistently. You’ll hear both “blue light scatters more” (the subject is the light) and “atmospheric molecules scatter blue light more” (the subject is the molecule). In any case, they means the same thing There's nothing ambiguous or inconsistent about this. In English…

In modern usage (e.g. in gaming communities) "carries" has become not only ambitransitive but also a noun.

If something "carries" or is "a carry", it means it is so strong it metaphorically carries the rest of the setup with it. For example:

> This card carries.

> These two are the carries of the team.

Re: Why is the sky blue?

#189

Post by lesostep »

int_19h wrote: post #161
reactordev wrote: post #152

Earlier quoted context omitted.

maybe in 100M years we'll get a 4th cone or rod. Probably from nuclear mutation...

There's some evidence that tetrachromacy already exists in a few humans. If so we have the gene already. But why would it spread?

fringe theory just for a bit of fun: since screen use 3 colors diodes, maybe people with tetrachromacy would be less addicted to screens, making them both more grounded in real life and marginally more successful, leading to them having more children?

I have no idea how to test it. But in my heart I know that screens with RG, GB or RB color models would suck enough that any screen addiction would be cured instantly.

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