The Yellow Sun

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Sure, the quality goes off as you magnify. If you start with better quality, you will end up with better. I thought you asked whether low quality could be magnified.
Ok, fair enough. :)

When I need to add an image, I will give them a try but see if I can get them to hold a better resolution. Otherwise, I think Postimages.com will be fine, but I have to remember to choose the proper link. I think I used the wrong one recently, which may have caused this discussion.
 
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Nov 24, 2022
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I think firstly that there appears to me, as I have observed it, that the sun appears yellow to our eyes, at least it does to mine. It seems quite different if I go to an indoor space with white light. Science surely begins with observation.

In theory it seems logical that light should contain all colours and therefore be white. But, as I have observed in my astrophotography over the last several years, stars have different colours due to their composition.

The light from stars, including our sun, changes with time also as we can see in red dwarfs, white dwarfs etc. So our star the sun will not be pure white.

Betelgeuse in Orion is a red colour to the eye and other stars are more white or yellow, or red...check some astrophotography images to see if this is true
 
I guess the real answer from an astronomer’s point of view would be ‘What is the color of the Sun?’ From an astronomer’s point of view with similar eyes on a planet orbiting another star, just as we classify stars from Earth. I guess it would be yellow, even though we perceive white from here.
 
I think firstly that there appears to me, as I have observed it, that the sun appears yellow to our eyes, at least it does to mine. It seems quite different if I go to an indoor space with white light. Science surely begins with observation.
Yes, during sunset's the Sun is always more yellow than at midday. If you do a pin-hole projection of an overhead Sun, you will see that it is white. The difference, of course, is due to the change in the amount of atmosphere sunlight must travel to reach us. Blue light scatters as a fourth power law, so very little atmosphere allows much more blue light to reach us, as in the mid-day Sun. This scattering of blue is why the sky is blue.

As you likely know given your photography knowledge, like camera software, our eyes will adjust to make a bright whitish light more white than otherwise. This allows us to color-adjust for various circumstances. If one looks at car head lights (old style lights) in bright daylight, they will have a strong yellow tint. But they will have only a slight yellow tint when seen at night. This is called "color constancy".

In theory it seems logical that light should contain all colours and therefore be white. But, as I have observed in my astrophotography over the last several years, stars have different colours due to their composition.
But all these different colored stars also emit contain all the colors. [This is a common error in logic even made by a surprising number of scientists and journalists who seem to have little interest in getting into the weeds with this topic.]

The light from stars, including our sun, changes with time also as we can see in red dwarfs, white dwarfs etc. So our star the sun will not be pure white.
Yes, ironically, it will someday actually be a yellow star, before it becomes more red, though Earth residents won't be around to see it. :)

Betelgeuse in Orion is a red colour to the eye and other stars are more white or yellow, or red...check some astrophotography images to see if this is true
Yes. The key to star color is their surface (photosphere) temperatures. Betelgeuse is much cooler than the Sun, which is much cooler than, say, Rigel, which has a blue tint. All O-class stars are very hot and emit more blue light than the color stars, so all three stars of the Orion belt (since we're in Orion at the moment) appear to have a blue tint to me.

But, atmospheric conditions can greatly effect color as well. Pollens, aerosols, dust, etc. all contribute to scattering. The more scattering the more objects shift in color toward red. I once saw a star hotter than the Sun have a strong yellow tint, and this was viewed from McDonald Obs. I was stunned, having made so many posts on how the Sun is only white, with no tint (if viewed from space; heliochromology). But the director of the observatory was with us and he said that sometimes they have to close the domes (protecting the scopes) due to excessive particle counts.

[BTW, thanks for your link! I look forward to someday getting serious with my coming new telescope by having imaging capability. So I need to start learning. I'll have more time later to enjoy your link.]

Also, notice my avatar. This is an accurate color image of the Sun taken off the projection table at the McMath-Pierce solar observatory. Notice that even the cooler (5000K) solar limb isn't yellow, and the center (6390K) has not blue ting. So this is evidence falsifies any yellow Sun hypothesis, but perhaps, in space, it has a slight blue center tint, though I doubt it.
 
I guess the real answer from an astronomer’s point of view would be ‘What is the color of the Sun?’ From an astronomer’s point of view with similar eyes on a planet orbiting another star, just as we classify stars from Earth. I guess it would be yellow, even though we perceive white from here.
This is why I think aliens can't seem to find us, per Fermi's Paradox. They are looking for a yellow star in order to find us, and we ain't got one. ;)
 
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Earlier in the thread I referred to a yelowish spot of light on the factory floor with the Sun high overhead. I make Procter and Gamble products including Charmin tissue and Bounty paper towels. Been doing so for 49 years in one capacity or another. I was once the youngest manager ever hired by the company, more recently I had the earliest hire date of the 1,700 people on site. Worked as a manager and "out on the floor" on and off from age 21 to age 69.
 
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Ah, now I recall. :) [I thought you might be offering something more on a personal level.]

I admire your 48 years at P&G! I've only worked for 47 years for a small equipment company that I took ownership of in '85, and I hope to be out at 48 yrs. of service as well. :)
 
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Unfortunately, I don't have 49 years of service, which is why I said: "On and off". Counting my P&G service and my service as a contractor I total only 26 years. However, if you include my years as a stockholder, yes, then it is 49. I left at age 45 with 24 years service and 12 times my annual salary in stock. Still have most of it, 25 years later. I still work whenever I get the chance though. Love working.
 
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