130
The colour of the Sun is white
(www.wtamu.edu)
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
this post was submitted on 01 Oct 2023
130 points (90.6% liked)
Today I Learned
18073 readers
184 users here now
What did you learn today? Share it with us!
We learn something new every day. This is a community dedicated to informing each other and helping to spread knowledge.
The rules for posting and commenting, besides the rules defined here for lemmy.world, are as follows:
Rules (interactive)
Rule 1- All posts must begin with TIL. Linking to a source of info is optional, but highly recommended as it helps to spark discussion.
** Posts must be about an actual fact that you have learned, but it doesn't matter if you learned it today. See Rule 6 for all exceptions.**
Rule 2- Your post subject cannot be illegal or NSFW material.
Your post subject cannot be illegal or NSFW material. You will be warned first, banned second.
Rule 3- Do not seek mental, medical and professional help here.
Do not seek mental, medical and professional help here. Breaking this rule will not get you or your post removed, but it will put you at risk, and possibly in danger.
Rule 4- No self promotion or upvote-farming of any kind.
That's it.
Rule 5- No baiting or sealioning or promoting an agenda.
Posts and comments which, instead of being of an innocuous nature, are specifically intended (based on reports and in the opinion of our crack moderation team) to bait users into ideological wars on charged political topics will be removed and the authors warned - or banned - depending on severity.
Rule 6- Regarding non-TIL posts.
Provided it is about the community itself, you may post non-TIL posts using the [META] tag on your post title.
Rule 7- You can't harass or disturb other members.
If you vocally harass or discriminate against any individual member, you will be removed.
Likewise, if you are a member, sympathiser or a resemblant of a movement that is known to largely hate, mock, discriminate against, and/or want to take lives of a group of people, and you were provably vocal about your hate, then you will be banned on sight.
For further explanation, clarification and feedback about this rule, you may follow this link.
Rule 8- All comments should try to stay relevant to their parent content.
Rule 9- Reposts from other platforms are not allowed.
Let everyone have their own content.
Rule 10- Majority of bots aren't allowed to participate here.
Unless included in our Whitelist for Bots, your bot will not be allowed to participate in this community. To have your bot whitelisted, please contact the moderators for a short review.
Partnered Communities
You can view our partnered communities list by following this link. To partner with our community and be included, you are free to message the moderators or comment on a pinned post.
Community Moderation
For inquiry on becoming a moderator of this community, you may comment on the pinned post of the time, or simply shoot a message to the current moderators.
founded 2 years ago
MODERATORS
White is defined by the color of the sun. Since we evolved within its light we of course see the distribution of wavelengths that make it down to Earth's surface as white. Even if the sun was always orange, we would see that as white instead.
Do you have a source for that claim? There is no way we can validate that without sending humans to another solar system. And wait thousands of years.
Surely it is plausible that an organism that evolved vision under particular lighting conditions would develop vision adapated to those lighting conditions.
I'm not telling you it's not worthwhile to come up with ways to test the claim if you want to be rigorous (e.g. you could measure the wavelength sensitivities of the vision of nocturnal or underwater animals and see if there's a pattern). But to me it's pretty self-evident as a starting point at least.
https://midwest.social/comment/3212652
Why do we see it as yellow, then?
Because our atmosphere causes "scattering" of hues in the highest frequencies. This is the same reason the sky appears blue.
Could also be redshift too. I don't know enough about it to know if we'd notice it over such a short distance and of a constant source, though. Definitely noticeable as reciprocity failure during long exposures in photography.
No, that's not at all what redshift is.
And neither redshift nor dopplershift would have that much effect on light at the speeds we're talking about.
Besides the sun's color on earth it's not a shift of wavelengths, it's a subtraction of wavelengths, as you easily can see in a spectrogram.
Do we experience Doppler shift with our own sun? I would assume as we are in a stable orbit we wouldnt
Strictly speaking since our orbit isn't a perfect circle we do move towards and away from the sun, so there will be some level of redshift. At those speeds there's really no chance of seeing it without specialised tools, in the same way you don't see redshift from a car driving past you.
Blue light gets scattered more by the atmosphere. So less blue light is received directly in a straight line from the sun and more is reflected from other parts of the sky. That's also why the sky looks blue in the day and why the evening sky looks red (if the sun is very low during the evening, the blue light can't reach you because it scattered so much due to the very long shallow way through the atmosphere)
During the day it's white, but it's also overhead and blindingly bright so we don't spend much time looking at it. As it gets closer to the horizon Rayleigh scattering begins filtering out the bluer light and the sun becomes yellow, then orange, then red. It also gets closer to our eyeline and becomes mildly safer to look at so we look at it a lot more. This in turn leads us to believe it's always yellow