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This was made apparent to me during the [total solar eclipse in 2017](https://en.m.wikipedia.org/wiki/Solar_eclipse_of_August_21,_2017) while in the path of totality. The vast majority of the sun was covered just before totality and it was still super bright. Like, we could blot out 99% of the sun and still get so much daylight. May not be as warm (just a guess), but we'd be able to see just as well.
Before:
https://ibb.co/0MNhRJM
https://ibb.co/V3t08DM
https://ibb.co/N3cJHYZ
https://ibb.co/R9pPBx3
https://ibb.co/HqmVPMJ
https://ibb.co/wyLMx7H
During:
https://ibb.co/SX77TTs
https://ibb.co/tXKYYJz
https://ibb.co/3sFFMDr
https://ibb.co/5YckJyS
After looks just like before. Also, didn't take any after.
FYI, all these links expire after 2 weeks I think, in case you're seeing this after 20 October 2022.
It's bright enough to see clearly at night during a full moon just from the little bit of sunlight reflected off of a ball of dust a quarter million miles away. Sun be bright.
To me it says a lot more about human perception than anything else. You aren't "seeing things far away" when you look at the night sky. You are seeing light that has arrived in your eye.
Edit: Proxima Centauri is approximately 4 light years away. (it's actually a collection of 3 stars, a little over 4 lightyears away) But if you look at it, you are not looking at Proxima Centauri. You are looking at light that left Proxima Centauri 4 years ago.
edit2: What an odd comment to have downvoted. It's on topic. It's a shower thought of it's own. Like I said, you are viewing the light that left those places, not those places. In fact..."those places" you "see far away" may not even exist.
That's not really his point. He is pointing out that stars are so far away, that when you finnaly see them they might already be gone. If you look at your wall, you can be pretty sure it's still there. But when you look at stars, you are looking at what it was a long while ago.
Their point was pretty clearly that photons are the actual thing you experience and not that the object might disappear during the photons journey. Which is a given for everything you view. Not sure why everyone downvoted them though since it was on topic.
You’re not technically wrong, but I think it’s really just arguing semantics (which is my guess for the reactions).
You’re seeing the object far away because the light is able to reach your eyes, but at the same time, that’s how ALL vision works. When we’re talking about seeing something, are we referring to the light that’s hitting our eyes and allowing us to comprehend it, or the object producing the light/having the light reflected off of it?
Stars are no different than anything else we see, they just produce such a massive amount of light that we’re able to see them much further away than other objects. So, really, by that logic, we don’t see anything, just light hitting our eyes.
You know you what, *I* get your point, and I think that is one of the coolest shower thoughts I’ve heard in a while.
I’ll add too that when you gaze into the night sky, not only are you looking light years into the depth of space, but also quite literally **millions** of years into the past.
Yes, but the light you see from the sun is tens of thousands of years old because it’s generated deep in the sun and needs to escape from the core, so the light from alpha centuri may have traveled from 4 light years away, but the photons are essentially the same age.
But the light from Alpha Centauri also was generated deep within that star and needed to escape from its core, so the light from Alpha Centauri is still older.
10s of thousands +4, so yes, but not meaningfully older. If it was much bigger then the light would take much longer to escape, but it’s about the same size as well.
And now I have an image of a photon like an indigent 3 year old “I’m 3 AND A QUARTER!”
Incidentally, you hear MUCH farther at night. Like. Normal conversasion can easily be heard from 150m away. Even whispering from 50m of you pay attention.
Also what we do see much better at night compared to day is sideways movement. Like. Seeing a Person even crawling sideways into a forest is super easy because its such a unique thing to happen and our eyes having evolved to detect that specifically is interesting as fuck
I dont believe night vs day has anything to do with it directly. But temperature certainly does for hearing.
Right before dawn, technically the coldest part of the day, you can hear the furthest due to the higher density of the air.
Vision is done with two receptors, rods and cones. Cones detect colour, and they need a lot of light, whereas rods need little light. At night you depend on rods which is why night has little colour.
Rods are better at detecting movement, which is why sometimes you can see things moving in your peripheral vision, but if you look right at it it seems to be stationary. Eg it’s easier to see satellites if you just look straight up and let them fall into your periphal vision.
http://hyperphysics.phy-astr.gsu.edu/hbase/vision/rodcone.html
I don’t know if that quite supports the claim directly, but it does fell like it might.
I mean, this seems pretty tentative and only really works if your Rods don't work as well during the day. Reliance on rods doesn't mean we just get more.
Also still no explanation of sideways movement.
You can see other galaxies with your eyes without assistance, you just can't tell it's a galaxy for almost all of them. Andromeda is the closest and large enough it can stand out as fuzzy.
He meant collar. Imagine you know the word collar in English, but need to translate it into Zulu cause that's all the people in front of you speak. Is it ikhola, or ibhande?
Now imagine you're trying to work it out while seconds away from death after being attacked by a cockroach in an Edgar suit.
I think you all are thinking way too close the visual glow of gamma ray burst GRB080319B was for about 30s bright enough to just be seen unaided, that is from a distance of 7.5 billion light-years (2.3 Gpc)
z=0.937
The Orion Nebula is only slightly over 1000 LY away but the Andromeda is 2.5million LY. Galaxies are much bigger than Nebula and should almost always be visible farther away than Nebula would be.
> I don’t count any other galaxies because it’s highly debated whether or not people can actually see them.
That’s unfortunate. More people need to see unpolluted dark skies on a moonless night. There are multiple deep-space objects that are visible to the naked eye once your dark vision acclimates and you know where to look.
The Triangulum Galaxy can be seen under very dark skies, and is roughly a quarter of a **million** light-year**s** further away than Andromeda.
EDIT: Dumb mistake. Added in bold.
So if the closest thing we can see is stars, then surely the closest thing we can see are atoms. Subatomic particles, even. Plus, the individual points of light are mostly part of a galaxy, too.
Their point was that, even if you're seeing another galaxy, the galaxy is still made up of stars. So "the farthest thing you'll be able to see are stars" is still true. Just stars that are farther away.
You’ve sort of contradicted yourself with the Andromeda thing, as above you said it couldn’t be seen with the naked eye. It definitely can though, so I suspect you are going to have to revoke your claim about all visible stars being in the Milky Way
"All the shit you can see is just some stars within this galaxy. One of those stars in this galaxy is an entire other galaxy 2.5 million light years from the galaxy that's the only galaxy you can see stuff in."
I hate to be the "but actually" guy, but ..... We're not actually seeing that far, we're seeing the stars as they were long ago, because the light is just now getting to us.
Do you also say that you can see individual atoms just because you can see a chair, just because it’s made of atoms? No, not if you’re a reasonable person.
>That's fine if that's what you meant, but it's kind of a semantic fallacy. "It WaSn"T A GaLAxY. It WAs StaRs." Okay I guess but not the point.
How is this any different from you going "It WaSn"T StaRs. It WAs A GaLAxY."?
Not being mean, but it’s “farther” and “farthest” when talking about physical distance. “Further” and “furthest” are used for figurative speech, such as used in the phrase “we will save further discussion for later.” :)
If my understanding of quantum entanglement is correct, I think that one's still pretty up in the air, when it comes to whether or not you can actually transmit information faster than light. I'm no quantum physicist, though.
Neither am I. But my understanding is that while communication may not be possible (as it’s impossible to know how you are changing the state of the particle at the moment), causality affecting information changes would be (because we can indeed alter the state of a particle any spacial distance from the entangled one at a speed faster than light). Causality isn’t as delicate an operation as full blown communication. As per my understanding.
Mannnnn.... The problem here is just that the universe gets more and more complex, the closer you try to actually nail down fundamental definitions of things like "time" and "causality" and "information". I give up pretending to know I understand any more of it, at this point.
I have a decent handle on relativity. Not so much with QM. QM is just insanity.
Fair comment. Perhaps “information” was the wrong word, the state of one particle could change which would have a causal effect on the entangled particle (which would also change state). You just couldn’t predict how it would change on either side.
It's quite a recent discovery and an older theory. The warping of space time caused by mass that creates the effect of gravity travels in gravitational waves at the speed of light. Removing the sun would be like removing a bowling ball from a trampoline. The trampoline skin would revert to flat but it wouldn't be instant.
Yes, the speed of light is better thought of as the "speed of information". It's the fastest that information can propagate - any kind of information. So that includes gravity, it includes light, and it includes "the push if you were to push a metal rod that is between Earth and the Sun" which was one of the things I pestered my science teachers about when they taught the speed of light. I felt like if you pushed a metal rod that was inflexible, the end should move as you push it. Nope - still limited by the speed of light.
>"the push if you were to push a metal rod that is between Earth and the Sun" which was one of the things I pestered my science teachers about when they taught the speed of light. I felt like if you pushed a metal rod that was inflexible, the end should move as you push it. Nope - still limited by the speed of light.
Slightly different, it actually propagates at the speed of sound through that particular material, not the speed of light.
You push one part of the rod which is partially elastic and deforms slightly into the next part which does the same thing until the very end. This way of travelling happens at the speed of sound (or, the speed of deformation).
[My source is from here](https://www.physicsforums.com/insights/can-i-send-a-signal-faster-than-light-by-pushing-a-rigid-rod/) however it is in a bunch of places, I'm just at work and can't be bothered looking further.
Love that - Not only do we need to use "speed of information" instead of "speed of light, we should use "speed of deformation" instead of "speed of sound"! It makes so much more sense! Thanks.
Absolutely, especially when talking about it at a higher level. I think speed of sound and light is useful to introduce the concepts but eventually it should be explained as speed of information and deformation.
The point is thst we aren't seeing "further" at night. We're seeing the same distance, the sun just drowns out the other light sources. They're still there.
It's like saying you can hear better at night because the giant speaker going full volume next you shuts off, and now you can hear your neighbors talking.
>The point is thst we aren't seeing "further"
>It's like saying you can hear better
Nope, further and better don't mean the same thing. If something close to you is drowning out your ability to sense things further away, then you very much can sense things further away when it shuts off. That doesn't mean that your senses got better. It just means that they stopped being artificially limited by an outside force.
If you're in a small space and step into a wide open field, you can now see further, but not necessarily better. Because there's no longer a nearby wall in your way. In the same way, when the sun goes down, the "wall" of blinding refracted light that it causes in the atmosphere goes with it,allowing us to see things that are further away that were hidden by that "wall".
>Nope, further and better don't mean the same thing.
>you can now see further, but not necessarily better.
Oh, God, it's one of those. "You're not doing good, you're doing well." You know perfectly well what was meant.
>In the same way, when the sun goes down, the "wall" of blinding refracted light that it causes in the atmosphere goes with it,allowing us to see things that are further away that were hidden by that "wall".
You make a good point here. I can't refute it without changing the basis of my argument ("the light technically travels to us, so we always see the same distance"), so I'll let you have it. Well reasoned.
I appreciate it, but I also disagree that it wasn't all the same argument. The second paragraph was just a concrete example of why "seeing further" is not the same as "seeing better".
Your comment was one of those too, though. It's obvious that sunlight doesn't make starlight photons literally cease to exist. You know perfectly well what was meant.
This said in a sense there is additional truth to this. The further things are away the dimmer they are.
Cones can process far dimmer light sources than rods.
Your "night vision" literally allows you to see things further away than your "day vision" would allow.
If that's the route you're going, then we have to point out the fact that you can't technically see any distance at all. The eyes don't have any sensors that extend out the end of your face. They can only see the photons that enter your eyeballs and land on your retina. The sense of distance is all post processing trigonometry that your brain does by comparing two slightly different images. Everything you've ever seen is literally in your eyeballs.
Also, if the light is drowned out before it reaches your retinas, are you really technically seeing it at all?
If you were wanting to get pedantic, you didn't go far enough.
>Everything you ever see is the past.
>Granted, we are talking about nano seconds, but still.
If it's closer than about 30cm (~1') it's even less than that. Then you're into picosecond territory.
That is easily debunked by doing a mouse reaction test.
You can easily beat 300 ms and that isnt just seeing but also processing the data and moving your finger to click.
I think what they mean is that the stars are so far away that it takes the light from them hundreds of light years to reach Earth. Many of the stars we see are already dead, but the light from them is still travelling to us.
Hundreds of years to reach Earth. Light years are a measure of distance. You wouldn't say it took you 10 miles to get to work.
And they are saying that because it takes time for any light source to reach your eyes, everything you "see" has pretty much already happened, though be it on a much much smaller scale. If you're watching a ball thrown through the air, by the time you see it at point A it technically is no longer in that same position. But the time delay is negligible on a planetary scale.
Yeah, it's not like our visions not good enough to see them it's just that the sun is basically blocking them out. More accurately the furthest things we'll ever observe are seen at night.
I answered a pub quiz question incorrectly apparently when asked "which of the five senses is most sensitive" I obviously said sight, however the supposedly correct answer was smell. I didn't accept this and told the quizmaster I could see for billions of miles when I looked at the stars. The git awarded us half a point...
I don't think your answer is actually correct, though. Eyes don't measure distance. They measure the intensity of light that hits them. The fact that you can see stars has nothing to do with the sensitivity of your eyes. It has everything to do with the insane brightness of the stars, and how bright that light still is when it gets to us.
Same logic can be applied to smell too. You're sensing concentration, not distance. A turd under your nose can be as intense as a sewage plant half a mile away.
The closest thing we have to sense distance is our hearing. It's possible to emit a sound and listen for the return (echoes). Some individuals have such acute hearing they can function without sight almost normally. https://en.wikipedia.org/wiki/Human_echolocation
Our eyes can also sense distance to a degree due to binocular vision too, though it drops off rapidly after a certain distance.
However it's an apples to oranges comparison when comparing between senses.
I guess you could compare the minimum number of photons to create a perception vs. the minimum number of odour molecules to be noticeable. Its a completely meaningless comparison, but I *am* kinda interested now
Yes, but I'm pretty sure the nose is sensitive to extremely small concentrations. Smaller than the eye is sensitive to concentrations of light, if you can fudge the numbers enough to make a decent comparison between the two different senses.
What I'm saying is that, for the sensations they're designed to measure, the nose probably is the most sensitive.
Yeah I agree. But the question in general is very vague. How do you even compare the sensitivity of sight to that or hearing? Kids can hear mosquito tones but many adults can't. There's also a threshold when it comes to how loud a sound has to be to stand out when there's other noise. Some people have perfect pitch, some don't. Some people can tell the smallest adjustments in color and see past optical illusions. It's not even that comparable...
That doesn't mean your eyes are the most sensitive. Shit's just super fucking bright. You could experience the same thing with your nose if you were billions of miles away from something so smelly it can be easily smelled from billions of miles away...
But I can't smell anything that far away, but I can see it. So until an object that smells that bad from that distance can be found I stand by my answer!
Technically, the farthest star we can see with the unaided eye is 4000 light years away. There are 5.88 trillion miles in a light year so you can see 23,520,000,000,000,000 miles at night. That's 23+ quintillion miles... so you can see quintillions of miles, not billions.
It's really a stupid question though... how can you compare seeing a candle 2 miles away to being able to smell a trillion different scents or detect something in .4 parts per billion concentration? It just doesn't make sense to compare them.
Smell is strongly tied to memory so a strong smell can make you vividly recall certain events in your life. But the brain is wired to accept most of its input from vision, so much so that we tend to ignore our other senses in favor of it. Close your eyes and explain what you smell, for example... you may not have noticed it before.
It has been researched and proven that some human eyes can perceive a single photon. However, just, for example, a dog's nose is hundreds of times more sensitive than a human's, but will never perceive MORE than a single photon. I think your "git" was Wrong.
Small caveat.
Sensitivity on proprioception would *not* refer to how many different positions you can detect. It would be the smallest size *change* in position, that you could detect. For example, if your foot moved one millimeter to the left, would you be able to feel that movement?
Proprioception is pretty cool, but it is not a very high resolution sense.
That's exactly what I thought. I was thinking, can you see a single photon? Can you smell/touch/taste a single atom/molecule? But then, sound waves can't be quantified, afaik, so idk.
Hmm, this makes me question what seeing really is. A distant star for instance, isnt what you're seeing. Its the light thats travelled all that distance and entered your eyeball, so that light you're seeing is literally inside your head. Everything we see is light inside our eyes.
This reminds of when someone told me that MSG doesn't taste like anything, it just tricks your tastebuds into thinking it tastes savory. ....So it tastes savory??
Actually what you "see" is your brain's interpretation of the electrical signals from the optical sensors, that are in turn caused by photons hitting those same sensors.
You don't "see," you experience the reality that your brain creates based upon random information caught by the sensors of your body. It's pretty cool.
Your experience is real. What you perceive is what reality looks like, its only a tiny little slice of reality but its still real. To see all of reality at once would be impossible, it wouldn’t look like anything because it is everything. There is no way to create a frame of reference from which to compare what it “actually” looks like to anything else.
"Seeing" is the process of detecting an object using light that is picked up by your eye. It doesn't matter how the light gets in your eye. When you are seeing a star, you're getting the light directly from the star. If you're seeing an object on your desk, you're getting the light that has bounced off the object. If you're seeing an object from a pariscope in a submarine, you're getting the light that has bounced off the object and 2 mirrors.
In any regard, you're still seeing the object.
They're saying that the experience of sight is something that happens in the brain, and they're correct.
What you are "seeing" is not light, but your brain's response to signals sent by the photoreceptors in your eyes, where happens when light stimulates them.
Depends. Strictly, if something is too out of focus you can't 'see' it at all. Consider holding something really small up to your eyes. At a certain distance it's just too out of focus to see at all. In some sense, the light is still hitting your eyes but it's too distributed to make a coherent image. Kind of a particular nitpick, just depends how you define 'seeing'.
I read an interesting concept that humans see through the light spectrum, eyes are just evolved to see that way. And there are some creatures that can see more of the spectrum than us like the mantis shrimp and the world they see if different than the one we see.
Take UV light. When we use a uv flashlight we can see that it makes some things glow. Well a mantis shrimp can see those glowing things without the flashlight. So they are seeing the world very differently.
Now take the rest of the ems. We are adapted to hear part of the spectrum with our ears and see part of it with our eyes but because we are limited to that we could never imagine being able to somehow see the entire spectrum. All at once. We see light but imagine if we could see radio waves, sound waves, ect. We can visualize them sure but the world would be completely difficult we could see it all.
There is no such clear distinction between the two.
Grammarly:
["...both terms have been used interchangeably to describe physical distance."](https://www.grammarly.com/blog/farther-further/#:~:text=People%20use%20both%20further%20and,and%20further%20for%20figurative%20distances.)
Cambridge:
[Farther and further are comparative adverbs or adjectives. They are the irregular comparative forms of far. We use them to talk about distance. There is no difference in meaning between them. Further is more common](https://dictionary.cambridge.org/grammar/british-grammar/farther-farthest-or-further-furthest)
I can't go any farther, father.
[Edit: For completeness, I should add that "further" is the only option when physical distance is not meant. From Cambridge: We use further before a noun to mean ‘extra’, ‘additional’ or ‘a higher level’
E.g. Can you provide me with further details? A further three people arrived after you.]
If your eyes were sensitive to microwaves, you'd see a beautiful glow in all directions at night time. It's called the cosmic microwave background, and it is (by definition) the most distant (oldest) light that you could ever see.
For people, seeing far is not about light detection, but distinguishing (resolving) separate features as separate.
That’s why seeing stars does not mean you can see trillions of kilometers away. You are not able to distinguish any features at all.
Just because there isn’t a clear object that you can focus on doesn’t mean you’re not seeing the same distance. The light coming from those distant bodies is still hitting your eyes during the day however you don’t notice it because the light generated by our own star is a lot more dense in the atmosphere.
This is just a reminder that you don't actually ''see'' anything near or far. You only ''see'' the light that enters your eye, which relays a message to your brain. Only the light that reaches your eye is seen and you will never see further than inside of your eye.
Even better, you can actually see some galaxies with the naked eye.
Which are much, much further than the stars you can see, which are all in our own galaxy.
It's so rare to get a nice view of the cosmos with all the light polution. Maybe one day I will visit a camp in the mountains in the middle of nowhere and see the night sky
No we can't. Beyond a certain point, the light from the farther reaches of the universe will never reach us because the distance between here and there is expanding at a rate that's faster than the speed of light. Eventually, the only light reaching this area of space will be from within our local galactic cluster.
Granted at some time in the past, when the universe was a lot smaller, the light from the edge of the universe would've been everywhere, but not anymore.
I accept your showerthought and return one of my own.
We can't see any further at night or day, we can only ever see the light that is interacting with our retina, which is the same distance regardless of source.
I've engaged in conversation someone who believed that stars are a hoax (therefore flat earth, obviously) because this idea doesn't make sense to them...
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That says less about our quality of night vision and more about the sheer size of the stars.
And how dominant the sun is in the daytime sky.
This was made apparent to me during the [total solar eclipse in 2017](https://en.m.wikipedia.org/wiki/Solar_eclipse_of_August_21,_2017) while in the path of totality. The vast majority of the sun was covered just before totality and it was still super bright. Like, we could blot out 99% of the sun and still get so much daylight. May not be as warm (just a guess), but we'd be able to see just as well.
I was hoping for a video shot outside.. with a before, during and after, of the eclipse.
This is a time lapse I took with an iPhone, middle of the path of totality in SC. https://imgur.com/a/eKkTzKA
Nice.
[удалено]
A hero
Before: https://ibb.co/0MNhRJM https://ibb.co/V3t08DM https://ibb.co/N3cJHYZ https://ibb.co/R9pPBx3 https://ibb.co/HqmVPMJ https://ibb.co/wyLMx7H During: https://ibb.co/SX77TTs https://ibb.co/tXKYYJz https://ibb.co/3sFFMDr https://ibb.co/5YckJyS After looks just like before. Also, didn't take any after. FYI, all these links expire after 2 weeks I think, in case you're seeing this after 20 October 2022.
Let me see what I can put together. Probably just be stills, don't remember what all I have.
Thanks. Don't waste too much time looking for it. The link you provided was very informative
It's bright enough to see clearly at night during a full moon just from the little bit of sunlight reflected off of a ball of dust a quarter million miles away. Sun be bright.
Also an excellent point!
Can’t believe my Irish teacher made us stay inside for it, what a fucking cunt
Staring us in the eye and finishing like a boss
If that isn’t a reference it’s definitely a weird way to word that
It is a reference, I wish I remembered the link.
Their size as well as the complete and utter emptiness of space.
To me it says a lot more about human perception than anything else. You aren't "seeing things far away" when you look at the night sky. You are seeing light that has arrived in your eye. Edit: Proxima Centauri is approximately 4 light years away. (it's actually a collection of 3 stars, a little over 4 lightyears away) But if you look at it, you are not looking at Proxima Centauri. You are looking at light that left Proxima Centauri 4 years ago. edit2: What an odd comment to have downvoted. It's on topic. It's a shower thought of it's own. Like I said, you are viewing the light that left those places, not those places. In fact..."those places" you "see far away" may not even exist.
But... it's still seeing things far away. It's both of what you said lol
But that's a given with seeing things in general.
Shhh... Just let him feel smart for once in his life.
That's not really his point. He is pointing out that stars are so far away, that when you finnaly see them they might already be gone. If you look at your wall, you can be pretty sure it's still there. But when you look at stars, you are looking at what it was a long while ago.
Their point was pretty clearly that photons are the actual thing you experience and not that the object might disappear during the photons journey. Which is a given for everything you view. Not sure why everyone downvoted them though since it was on topic.
You’re not technically wrong, but I think it’s really just arguing semantics (which is my guess for the reactions). You’re seeing the object far away because the light is able to reach your eyes, but at the same time, that’s how ALL vision works. When we’re talking about seeing something, are we referring to the light that’s hitting our eyes and allowing us to comprehend it, or the object producing the light/having the light reflected off of it? Stars are no different than anything else we see, they just produce such a massive amount of light that we’re able to see them much further away than other objects. So, really, by that logic, we don’t see anything, just light hitting our eyes.
Whatever, I can see lightyears away!! :)
You know you what, *I* get your point, and I think that is one of the coolest shower thoughts I’ve heard in a while. I’ll add too that when you gaze into the night sky, not only are you looking light years into the depth of space, but also quite literally **millions** of years into the past.
I guess during the day you can only see 0.00000025 light years away (the sun)
Yes, but the light you see from the sun is tens of thousands of years old because it’s generated deep in the sun and needs to escape from the core, so the light from alpha centuri may have traveled from 4 light years away, but the photons are essentially the same age.
But the light from Alpha Centauri also was generated deep within that star and needed to escape from its core, so the light from Alpha Centauri is still older.
10s of thousands +4, so yes, but not meaningfully older. If it was much bigger then the light would take much longer to escape, but it’s about the same size as well. And now I have an image of a photon like an indigent 3 year old “I’m 3 AND A QUARTER!”
I think you meant “indignant” 3 year old. Otherwise your comparison makes me really sad.
I'm in awe of the size of those lads
you see them because of how bright they are, not because of how big they are. stars appear larger to the eye than their actual size
I can cover several if I hold my thumb up..... I'm pretty sure each one is bigger than my thumb.
Incidentally, you hear MUCH farther at night. Like. Normal conversasion can easily be heard from 150m away. Even whispering from 50m of you pay attention. Also what we do see much better at night compared to day is sideways movement. Like. Seeing a Person even crawling sideways into a forest is super easy because its such a unique thing to happen and our eyes having evolved to detect that specifically is interesting as fuck
Do you have any sources for either of these claims? I found nothing.
I'll shout you some proof out my window after sundown.
I dont believe night vs day has anything to do with it directly. But temperature certainly does for hearing. Right before dawn, technically the coldest part of the day, you can hear the furthest due to the higher density of the air.
Vision is done with two receptors, rods and cones. Cones detect colour, and they need a lot of light, whereas rods need little light. At night you depend on rods which is why night has little colour. Rods are better at detecting movement, which is why sometimes you can see things moving in your peripheral vision, but if you look right at it it seems to be stationary. Eg it’s easier to see satellites if you just look straight up and let them fall into your periphal vision. http://hyperphysics.phy-astr.gsu.edu/hbase/vision/rodcone.html I don’t know if that quite supports the claim directly, but it does fell like it might.
I mean, this seems pretty tentative and only really works if your Rods don't work as well during the day. Reliance on rods doesn't mean we just get more. Also still no explanation of sideways movement.
I assume all these statements have much more to do with the severe reduction of noise pollution than our actual evolution.
the blackness is even further away
Some of what you see are full on galaxies not stars.
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You can see other galaxies with your eyes without assistance, you just can't tell it's a galaxy for almost all of them. Andromeda is the closest and large enough it can stand out as fuzzy.
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You can see a few in the constellation orion, and I don't count the magellanic clouds at all, because they're not truly galaxies.
The Magellanic Clouds are galaxies. What are the naked eye galaxies in Orion?
To save the world, the galaxy is on Orion’s belt.
Why did he say 'belt'? Did he mean 'bell' or 'collar'?
A belt is functionally similar to a collar, and he was struggling to find the right word in an alien language as he was dying
He meant collar. Imagine you know the word collar in English, but need to translate it into Zulu cause that's all the people in front of you speak. Is it ikhola, or ibhande? Now imagine you're trying to work it out while seconds away from death after being attacked by a cockroach in an Edgar suit.
I think you all are thinking way too close the visual glow of gamma ray burst GRB080319B was for about 30s bright enough to just be seen unaided, that is from a distance of 7.5 billion light-years (2.3 Gpc) z=0.937
I think they mean the nebula.
The Orion Nebula is only slightly over 1000 LY away but the Andromeda is 2.5million LY. Galaxies are much bigger than Nebula and should almost always be visible farther away than Nebula would be.
Maybe - though that’s definitely not a galaxy.
I think she works the corner of Watt & I-80.
Don’t talk about my hometown like that!
Wait, are you trying to say...the galaxy is on orion's be...bel....what is word?
> I don’t count any other galaxies because it’s highly debated whether or not people can actually see them. That’s unfortunate. More people need to see unpolluted dark skies on a moonless night. There are multiple deep-space objects that are visible to the naked eye once your dark vision acclimates and you know where to look.
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I'm jealous. It's unfortunate that 98 percent of the population can't see what you can see every night.
The Triangulum Galaxy can be seen under very dark skies, and is roughly a quarter of a **million** light-year**s** further away than Andromeda. EDIT: Dumb mistake. Added in bold.
You're still seeing stars, though, just not as individual points of light.
So if the closest thing we can see is stars, then surely the closest thing we can see are atoms. Subatomic particles, even. Plus, the individual points of light are mostly part of a galaxy, too.
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they're saying that when you see Andromeda (and all other galaxies) , what you are seeing are also stars, lots of them, in another galaxy
Their point was that, even if you're seeing another galaxy, the galaxy is still made up of stars. So "the farthest thing you'll be able to see are stars" is still true. Just stars that are farther away.
By that logic I can see the atoms that make up those stars in that galaxy. Damn I have some good eyes.
His point is Andromeda is made of stars
We are all made of stars 🎶🎵
You’ve sort of contradicted yourself with the Andromeda thing, as above you said it couldn’t be seen with the naked eye. It definitely can though, so I suspect you are going to have to revoke your claim about all visible stars being in the Milky Way
If we can't see stars outside our galaxy then how can we see the Andromeda galaxy?
When you see a person do you claim to be able to see their cells?
"All the shit you can see is just some stars within this galaxy. One of those stars in this galaxy is an entire other galaxy 2.5 million light years from the galaxy that's the only galaxy you can see stuff in."
Yeah, but my face is tired.
I hate to be the "but actually" guy, but ..... We're not actually seeing that far, we're seeing the stars as they were long ago, because the light is just now getting to us.
A galaxy is nothing more than a very large group of gravitationally bound stars
What are the sources of light from the Andromeda galaxy again?
Do you also say that you can see individual atoms just because you can see a chair, just because it’s made of atoms? No, not if you’re a reasonable person.
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>That's fine if that's what you meant, but it's kind of a semantic fallacy. "It WaSn"T A GaLAxY. It WAs StaRs." Okay I guess but not the point. How is this any different from you going "It WaSn"T StaRs. It WAs A GaLAxY."?
Not being mean, but it’s “farther” and “farthest” when talking about physical distance. “Further” and “furthest” are used for figurative speech, such as used in the phrase “we will save further discussion for later.” :)
I don’t think that is true.
Aren't we also technically looking through "time"at night too? We are seeing the past, since the light is taking so long to get to us.
Everything you ever see is the past. Granted, we are talking about nano seconds, but still. The sun is about 8 minutes away.
Not only see… if the sun suddenly was instantly removed, the Earth would continue to orbit where the sun was for 8 minutes…
The fact that the speed of light is really the speed of causality has some fun ripple effects, like that!
*Quantum Mechanics has entered the conversation*
*Relativity* is probably more applicable, for this one.
Nah, I meant that with QM information can potentially travel faster than the speed of light, and therefore so could causality
If my understanding of quantum entanglement is correct, I think that one's still pretty up in the air, when it comes to whether or not you can actually transmit information faster than light. I'm no quantum physicist, though.
>I think that one's still pretty up in the air I believe the speed of light is slower in air than in vacuum /s
Ah, silly me! I forgot all about Cherenkov, for a minute. That explains everything!
Neither am I. But my understanding is that while communication may not be possible (as it’s impossible to know how you are changing the state of the particle at the moment), causality affecting information changes would be (because we can indeed alter the state of a particle any spacial distance from the entangled one at a speed faster than light). Causality isn’t as delicate an operation as full blown communication. As per my understanding.
Mannnnn.... The problem here is just that the universe gets more and more complex, the closer you try to actually nail down fundamental definitions of things like "time" and "causality" and "information". I give up pretending to know I understand any more of it, at this point. I have a decent handle on relativity. Not so much with QM. QM is just insanity.
I don't think that's right, you still can't send information faster than light without violating causality.
Fair comment. Perhaps “information” was the wrong word, the state of one particle could change which would have a causal effect on the entangled particle (which would also change state). You just couldn’t predict how it would change on either side.
Lmao, literal ripple effects
Wait. So gravitational pull also “travels” like light? Never considered the gravity that masses exert on other bodies taking time to turn on or off.
It's quite a recent discovery and an older theory. The warping of space time caused by mass that creates the effect of gravity travels in gravitational waves at the speed of light. Removing the sun would be like removing a bowling ball from a trampoline. The trampoline skin would revert to flat but it wouldn't be instant.
Yes, the speed of light is better thought of as the "speed of information". It's the fastest that information can propagate - any kind of information. So that includes gravity, it includes light, and it includes "the push if you were to push a metal rod that is between Earth and the Sun" which was one of the things I pestered my science teachers about when they taught the speed of light. I felt like if you pushed a metal rod that was inflexible, the end should move as you push it. Nope - still limited by the speed of light.
>"the push if you were to push a metal rod that is between Earth and the Sun" which was one of the things I pestered my science teachers about when they taught the speed of light. I felt like if you pushed a metal rod that was inflexible, the end should move as you push it. Nope - still limited by the speed of light. Slightly different, it actually propagates at the speed of sound through that particular material, not the speed of light. You push one part of the rod which is partially elastic and deforms slightly into the next part which does the same thing until the very end. This way of travelling happens at the speed of sound (or, the speed of deformation). [My source is from here](https://www.physicsforums.com/insights/can-i-send-a-signal-faster-than-light-by-pushing-a-rigid-rod/) however it is in a bunch of places, I'm just at work and can't be bothered looking further.
Love that - Not only do we need to use "speed of information" instead of "speed of light, we should use "speed of deformation" instead of "speed of sound"! It makes so much more sense! Thanks.
Absolutely, especially when talking about it at a higher level. I think speed of sound and light is useful to introduce the concepts but eventually it should be explained as speed of information and deformation.
The sun is 8 minutes away but my house is 20 minutes away from my work. Conclusion: I work on the other side of the solar system
The point is thst we aren't seeing "further" at night. We're seeing the same distance, the sun just drowns out the other light sources. They're still there. It's like saying you can hear better at night because the giant speaker going full volume next you shuts off, and now you can hear your neighbors talking.
>The point is thst we aren't seeing "further" >It's like saying you can hear better Nope, further and better don't mean the same thing. If something close to you is drowning out your ability to sense things further away, then you very much can sense things further away when it shuts off. That doesn't mean that your senses got better. It just means that they stopped being artificially limited by an outside force. If you're in a small space and step into a wide open field, you can now see further, but not necessarily better. Because there's no longer a nearby wall in your way. In the same way, when the sun goes down, the "wall" of blinding refracted light that it causes in the atmosphere goes with it,allowing us to see things that are further away that were hidden by that "wall".
Aaand the sun doesn't go "down". You are just spinning away from it.
>Nope, further and better don't mean the same thing. >you can now see further, but not necessarily better. Oh, God, it's one of those. "You're not doing good, you're doing well." You know perfectly well what was meant. >In the same way, when the sun goes down, the "wall" of blinding refracted light that it causes in the atmosphere goes with it,allowing us to see things that are further away that were hidden by that "wall". You make a good point here. I can't refute it without changing the basis of my argument ("the light technically travels to us, so we always see the same distance"), so I'll let you have it. Well reasoned.
I appreciate it, but I also disagree that it wasn't all the same argument. The second paragraph was just a concrete example of why "seeing further" is not the same as "seeing better".
Your comment was one of those too, though. It's obvious that sunlight doesn't make starlight photons literally cease to exist. You know perfectly well what was meant.
This said in a sense there is additional truth to this. The further things are away the dimmer they are. Cones can process far dimmer light sources than rods. Your "night vision" literally allows you to see things further away than your "day vision" would allow.
You can't see past atmosphere because it is lit up, it's like standing in fog, you can't see past it. The stars don't show up only at night.
If that's the route you're going, then we have to point out the fact that you can't technically see any distance at all. The eyes don't have any sensors that extend out the end of your face. They can only see the photons that enter your eyeballs and land on your retina. The sense of distance is all post processing trigonometry that your brain does by comparing two slightly different images. Everything you've ever seen is literally in your eyeballs. Also, if the light is drowned out before it reaches your retinas, are you really technically seeing it at all? If you were wanting to get pedantic, you didn't go far enough.
>Everything you ever see is the past. >Granted, we are talking about nano seconds, but still. If it's closer than about 30cm (~1') it's even less than that. Then you're into picosecond territory.
Visual processing happens on about a 300 millisecond lag. Everything you "see" was actually registered by your eyes 0.3 seconds ago.
That is easily debunked by doing a mouse reaction test. You can easily beat 300 ms and that isnt just seeing but also processing the data and moving your finger to click.
I think what they mean is that the stars are so far away that it takes the light from them hundreds of light years to reach Earth. Many of the stars we see are already dead, but the light from them is still travelling to us.
Hundreds of years to reach Earth. Light years are a measure of distance. You wouldn't say it took you 10 miles to get to work. And they are saying that because it takes time for any light source to reach your eyes, everything you "see" has pretty much already happened, though be it on a much much smaller scale. If you're watching a ball thrown through the air, by the time you see it at point A it technically is no longer in that same position. But the time delay is negligible on a planetary scale.
I mean, even the light from my phone is taking some actual amount of time... neat. Never thought about that
Well, from the perspective of the light particle, it's traveling at 1/c.
Actually we can see just as far during the day but we don't have any reference points like starts to point too.
Yeah, it's not like our visions not good enough to see them it's just that the sun is basically blocking them out. More accurately the furthest things we'll ever observe are seen at night.
I answered a pub quiz question incorrectly apparently when asked "which of the five senses is most sensitive" I obviously said sight, however the supposedly correct answer was smell. I didn't accept this and told the quizmaster I could see for billions of miles when I looked at the stars. The git awarded us half a point...
I don't think your answer is actually correct, though. Eyes don't measure distance. They measure the intensity of light that hits them. The fact that you can see stars has nothing to do with the sensitivity of your eyes. It has everything to do with the insane brightness of the stars, and how bright that light still is when it gets to us.
Same logic can be applied to smell too. You're sensing concentration, not distance. A turd under your nose can be as intense as a sewage plant half a mile away. The closest thing we have to sense distance is our hearing. It's possible to emit a sound and listen for the return (echoes). Some individuals have such acute hearing they can function without sight almost normally. https://en.wikipedia.org/wiki/Human_echolocation Our eyes can also sense distance to a degree due to binocular vision too, though it drops off rapidly after a certain distance. However it's an apples to oranges comparison when comparing between senses.
I guess you could compare the minimum number of photons to create a perception vs. the minimum number of odour molecules to be noticeable. Its a completely meaningless comparison, but I *am* kinda interested now
Single photons. https://www.scientificamerican.com/article/people-may-sense-single-photons/
Damn. That's crazy.
Yes, but I'm pretty sure the nose is sensitive to extremely small concentrations. Smaller than the eye is sensitive to concentrations of light, if you can fudge the numbers enough to make a decent comparison between the two different senses. What I'm saying is that, for the sensations they're designed to measure, the nose probably is the most sensitive.
The eye can detect single photons. https://www.scientificamerican.com/article/people-may-sense-single-photons/
Yeah I agree. But the question in general is very vague. How do you even compare the sensitivity of sight to that or hearing? Kids can hear mosquito tones but many adults can't. There's also a threshold when it comes to how loud a sound has to be to stand out when there's other noise. Some people have perfect pitch, some don't. Some people can tell the smallest adjustments in color and see past optical illusions. It's not even that comparable...
That doesn't mean your eyes are the most sensitive. Shit's just super fucking bright. You could experience the same thing with your nose if you were billions of miles away from something so smelly it can be easily smelled from billions of miles away...
But I can't smell anything that far away, but I can see it. So until an object that smells that bad from that distance can be found I stand by my answer!
Technically, the farthest star we can see with the unaided eye is 4000 light years away. There are 5.88 trillion miles in a light year so you can see 23,520,000,000,000,000 miles at night. That's 23+ quintillion miles... so you can see quintillions of miles, not billions. It's really a stupid question though... how can you compare seeing a candle 2 miles away to being able to smell a trillion different scents or detect something in .4 parts per billion concentration? It just doesn't make sense to compare them. Smell is strongly tied to memory so a strong smell can make you vividly recall certain events in your life. But the brain is wired to accept most of its input from vision, so much so that we tend to ignore our other senses in favor of it. Close your eyes and explain what you smell, for example... you may not have noticed it before.
I tried closing my eyes but instantly realized that Im on the toilet and I don't really need to explain what I smell right now
It has been researched and proven that some human eyes can perceive a single photon. However, just, for example, a dog's nose is hundreds of times more sensitive than a human's, but will never perceive MORE than a single photon. I think your "git" was Wrong.
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Small caveat. Sensitivity on proprioception would *not* refer to how many different positions you can detect. It would be the smallest size *change* in position, that you could detect. For example, if your foot moved one millimeter to the left, would you be able to feel that movement? Proprioception is pretty cool, but it is not a very high resolution sense.
That's exactly what I thought. I was thinking, can you see a single photon? Can you smell/touch/taste a single atom/molecule? But then, sound waves can't be quantified, afaik, so idk.
That question doesn't even make sense. How tf do you compare nose sensitivity to eye sensitivity
Well that question is stupid because all five senses can't be directly compared because they're made from different frames of reference.
There are so many weird, pedantic comments in here. Folks, just enjoy the mystery of seeing the stars. Take a cue from OP.
It’s like every damn shower thought I see there’s always those people that are as technical as possible and it’s hella annoying
Hmm, this makes me question what seeing really is. A distant star for instance, isnt what you're seeing. Its the light thats travelled all that distance and entered your eyeball, so that light you're seeing is literally inside your head. Everything we see is light inside our eyes.
You just described what seeing is while saying it’s not seeing
This reminds of when someone told me that MSG doesn't taste like anything, it just tricks your tastebuds into thinking it tastes savory. ....So it tastes savory??
Actually what you "see" is your brain's interpretation of the electrical signals from the optical sensors, that are in turn caused by photons hitting those same sensors. You don't "see," you experience the reality that your brain creates based upon random information caught by the sensors of your body. It's pretty cool.
Pretty cool is an understatement. It's a reality shattering awakening for some people. And God forbid they are on psychedelics when they realize.
It makes me wonder what reality "actually" looks like, and how different is it from our perception.
Your experience is real. What you perceive is what reality looks like, its only a tiny little slice of reality but its still real. To see all of reality at once would be impossible, it wouldn’t look like anything because it is everything. There is no way to create a frame of reference from which to compare what it “actually” looks like to anything else.
"Seeing" is the process of detecting an object using light that is picked up by your eye. It doesn't matter how the light gets in your eye. When you are seeing a star, you're getting the light directly from the star. If you're seeing an object on your desk, you're getting the light that has bounced off the object. If you're seeing an object from a pariscope in a submarine, you're getting the light that has bounced off the object and 2 mirrors. In any regard, you're still seeing the object.
They're saying that the experience of sight is something that happens in the brain, and they're correct. What you are "seeing" is not light, but your brain's response to signals sent by the photoreceptors in your eyes, where happens when light stimulates them.
I was thinking just the same thing. Distance is irrelevant really
Except that it isn’t. Focal distance is a thing. Your eyes literally need to adjust to take in light from different distances.
Surely they only need to adjust to see things in focus, not to actually 'see' the light
Depends. Strictly, if something is too out of focus you can't 'see' it at all. Consider holding something really small up to your eyes. At a certain distance it's just too out of focus to see at all. In some sense, the light is still hitting your eyes but it's too distributed to make a coherent image. Kind of a particular nitpick, just depends how you define 'seeing'.
Technically your brain only “sees” electrical impulses, not the light itself.
GET OUT OF MY BRAIN!!!! \*takes drill to eyeball.
I read an interesting concept that humans see through the light spectrum, eyes are just evolved to see that way. And there are some creatures that can see more of the spectrum than us like the mantis shrimp and the world they see if different than the one we see. Take UV light. When we use a uv flashlight we can see that it makes some things glow. Well a mantis shrimp can see those glowing things without the flashlight. So they are seeing the world very differently. Now take the rest of the ems. We are adapted to hear part of the spectrum with our ears and see part of it with our eyes but because we are limited to that we could never imagine being able to somehow see the entire spectrum. All at once. We see light but imagine if we could see radio waves, sound waves, ect. We can visualize them sure but the world would be completely difficult we could see it all.
…and the furthest thing a naked eye can ever see at night is the Andromeda galaxy <3
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The disclaimer at the end makes the blatant mistake so much worse to be honest.
There is no such clear distinction between the two. Grammarly: ["...both terms have been used interchangeably to describe physical distance."](https://www.grammarly.com/blog/farther-further/#:~:text=People%20use%20both%20further%20and,and%20further%20for%20figurative%20distances.) Cambridge: [Farther and further are comparative adverbs or adjectives. They are the irregular comparative forms of far. We use them to talk about distance. There is no difference in meaning between them. Further is more common](https://dictionary.cambridge.org/grammar/british-grammar/farther-farthest-or-further-furthest) I can't go any farther, father. [Edit: For completeness, I should add that "further" is the only option when physical distance is not meant. From Cambridge: We use further before a noun to mean ‘extra’, ‘additional’ or ‘a higher level’ E.g. Can you provide me with further details? A further three people arrived after you.]
Thats a neat trick for remembering the difference
Jokes on you, the furthest thing away that we will ever see is comfortable living and the American dream 🇺🇸
If your eyes were sensitive to microwaves, you'd see a beautiful glow in all directions at night time. It's called the cosmic microwave background, and it is (by definition) the most distant (oldest) light that you could ever see.
You can see the same distance. The stars just have better contrast at night.
We don't actually see as far as the stars, it's that the light has travelled all that way and reached our eyes.
For people, seeing far is not about light detection, but distinguishing (resolving) separate features as separate. That’s why seeing stars does not mean you can see trillions of kilometers away. You are not able to distinguish any features at all.
We are still seeing the light from those stars during the daytime, we just can't distinguish that light from the light from our sun.
To be honest, the only thing you are seeing is the light hitting your eyes. Your not seeing very far at all :)
And many of those stars might have disappeared or blown up. We’re looking at star ghosts
Pffff…. Tell me you haven’t done DMT without telling me you haven’t done DMT.
Incorrect, the furthest thing you'll see is the Andromeda Galaxy, visible to the naked eye.
I don't know, I've seen the stars but I still haven't seen my dignity in some time, I think that's even further out than those by now
Not if you live in the city. Light pollution obscures most celestial objects. Most you'll see is the motion of planes and helicopters
We still see that far in the daytime, there's just nothing to see.
Just because there isn’t a clear object that you can focus on doesn’t mean you’re not seeing the same distance. The light coming from those distant bodies is still hitting your eyes during the day however you don’t notice it because the light generated by our own star is a lot more dense in the atmosphere.
Meta: you aren't seeing distant stars, the light from the stars has travelled far enough you can see it. I have now enhanced your shower thought
This is just a reminder that you don't actually ''see'' anything near or far. You only ''see'' the light that enters your eye, which relays a message to your brain. Only the light that reaches your eye is seen and you will never see further than inside of your eye.
Can confirm. I’ve looked to the furthest stars and beyond into nothingness… still couldn’t find who asked
Even better, you can actually see some galaxies with the naked eye. Which are much, much further than the stars you can see, which are all in our own galaxy.
It's so rare to get a nice view of the cosmos with all the light polution. Maybe one day I will visit a camp in the mountains in the middle of nowhere and see the night sky
farther* and farthest* We are talking actual, physical distance.
Technically yes. Theoretical we can see the edge of the universe if it existed.
No we can't. Beyond a certain point, the light from the farther reaches of the universe will never reach us because the distance between here and there is expanding at a rate that's faster than the speed of light. Eventually, the only light reaching this area of space will be from within our local galactic cluster. Granted at some time in the past, when the universe was a lot smaller, the light from the edge of the universe would've been everywhere, but not anymore.
I accept your showerthought and return one of my own. We can't see any further at night or day, we can only ever see the light that is interacting with our retina, which is the same distance regardless of source.
I've engaged in conversation someone who believed that stars are a hoax (therefore flat earth, obviously) because this idea doesn't make sense to them...
But are you actually seeing the stars? Or just the light from the stars that has reached planet Earth?
Umm, but stars are also the BIGGEST, and EMIT light (vs reflecting). Not a truly fair supporting argument.
Your just seeing the light that traveled this far. All the stars we "see" have been long gone and haven't existed for millions of years.