Is it possible to see the stars in the sky?

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The discussion revolves around the concept of "seeing" stars and the sun, focusing on the physics of light and perception. Participants explore whether observing celestial bodies means seeing them as they are in the present or as they were in the past due to the time it takes for light to reach Earth. The conversation touches on relativity, noting that when looking at stars, one is seeing light emitted long ago, with some stars possibly no longer existing. The idea that perception is influenced by distance and time is emphasized, leading to debates about the nature of "seeing" and whether it is meaningful to consider the past light when discussing visibility. The thread also humorously diverges into personal anecdotes and philosophical musings about perception and reality, ultimately questioning the shared experience of seeing among individuals.
  • #31
russ_watters said:
Wow, post 21. That's pathetic, guys.

I want to know: have you ever seen the rain?
Hey, watch who you call pathetic. At least I knew where he was going with the elapsed time.
 
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  • #32
OK so I don't really get the point of this thread, but since it is started already...

When I look in the direction of the stars I collect light that is emitted by it. This is a very small portion of all the radiation, first a small part of the electromagnetic spectrum, second ignoring all matter radiation, so I collect only a very limited amount of information. On top of that, the visible electromagnetic spectrum emitted by the star is not necessarilly the same as the one received at the level of the ground on Earth. But let us concentrate only on the visible part of the electromagnetic spectrum just outside the star, ignoring the time it takes to travel and the redshift it undergoes so doing, ignoring again the diffusion it undergoes in the atmosphere of the Earth... This radiation is not strictly emitted by the entire star, but rather only the photosphere, the region where it becomes transparent to the part of the spectrum we are talking about here.

Am I getting closer to what you expect ?
 
  • #33
Evo said:
When you look at a star, you are seeing the light that it gave off in the past, how long ago depends on the distance. Some stars that we "see" today may no longer exist.

I knew about this, but I'm still lost at where this thread is going. Since if this was the complete answer it would be over by now! I really want to know the answer to this...
 
  • #34
G01 said:
I knew about this, but I'm still lost at where this thread is going. Since if this was the complete answer it would be over by now! I really want to know the answer to this...
I have no clue what he's looking for either. It's like me asking...what am I thinking of when I think of the sun? :rolleyes:
 
  • #35
chroot said:
Well, the theory of relativity abolishes the notion of absolute time. It is meaningless to ask about the state of a distant object "right now," as the concept of "right now" doesn't extend beyond your own frame of reference.
Now you're talking. :biggrin:
 
  • #36
you are seeing the past, you are seeing history. everything we see is what was , not what is. Our processing is not fast enough to see now..only then.
 
  • #37
hi, you are seeing a ""place"" or position of that star at some time from the past, which you all will agree with that. BUT CAN YOU BELIEVE that this was noted in a book that is 1400 years old?
 
  • #38
angel 42 said:
hi, you are seeing a ""place"" or position of that star at some time from the past, which you all will agree with that. BUT CAN YOU BELIEVE that this was noted in a book that is 1400 years old?
A lot of guesses and sometimes just stories that in hindsight have some truth to them, but it wasn't the result of scientific research, and no, I am not surprised. We just discussed this kind of thing in another thread.
 
  • #39
angel 42 said:
BUT CAN YOU BELIEVE that this was noted in a book that is 1400 years old?

We were supposed to get this from the original question posted?

hi, can anyone of you look and see the stars, for example, can you see the sun?
kind of a puzzle
lets see what do you think

If we were, how?
 
  • #40
angel 42 said:
hi, you are seeing a ""place"" or position of that star at some time from the past, which you all will agree with that. BUT CAN YOU BELIEVE that this was noted in a book that is 1400 years old?

Are you impressed about this bit of triviality because it is ancient? Dude, here's another one: you see what you're seeing "from another place at another time". Cool, hey? Gosh, this was time well wasted...
 
  • #42
russ_watters said:
Have you seen the bridge?


I ain't seen the bridge!

Where's that confounded bridge?
 
  • #43
at least you do agree that what you see is a postion of the star...
 
  • #44
Angel_42, you're not making much sense.

By definition, "seeing" something is sensing light coming ~directly from it. Therefore when you look at the sun you're seeing the sun. You can argue that really you're only seeing photons representing the sun in the past, and this is of course true, but that's true of EVERYTHING you see.
 
  • #45
Really now...

This kind of word play is pointless and, no offense intended, the type of thing I heard from my young children.
<flash-back theme>
Son: "Can I see that toy?"
Daughter: (holding the toy in front of her brother) "There you go, you can see it!"
Son: (exasperated) "No, I want to hold it."
Daughter: "You didn't say "hold it, you said "see it"...

If someone has the ability of sight, and the weather and time are right, if you look at the sun, you see it regardless of our distance from it, or its true relative position. Whether you see the sun as it was 8 minutes ago or in some different location is not relevant to the question "Can you see the sun?" They are just modifiers to the object we call the "sun". Let's apply the same standard to a much closer object, say... a car. You and I can be standing side by side as a blue car passes in front of us. I ask, "Did you see that car?" You reply, "Yes." It would be unreasonable for me to say, "No, you saw a Blue car." The fact that sun is 8 light minutes away or that the car was blue did not change the truth that both were observed.

...and everything under the sun is in tune
but the sun is eclipsed by the moon.
 
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  • #46
Okay, the only thing I can figure he's looking for is that because of the delay in when you see the light from the sun vs when it was emitted from the sun, when you look in the direction you see the light coming from, it's where the sun WAS when the light was emitted, not it's actual location NOW. It might be a bigger difference for more distant stars, but really fairly inconsequential for the position of the sun relative to wherever you're standing attempting to blind yourself staring at it. :rolleyes:
 
  • #47
I thought this had been locked.

Locked now.
 

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