The Light From a Star: Comparing Photons & Travel Distance

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Photons emitted by stars and those from man-made sources are fundamentally the same, as they do not differ in their properties. The key factor in the visibility of starlight is the sheer number of photons emitted, which diminishes in intensity as they spread over greater distances due to the inverse-square law. Photons do not decay; instead, they can be absorbed or scattered, which affects their visibility. The concept of "dilution rate" refers to how light appears less bright at greater distances due to fewer photons reaching an observer. Overall, both natural and artificial light sources produce stable photons that travel at the same speed until they interact with matter.
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What is different about the photons from a star compared to something man-made which allows it to travel so far?
 
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dizam said:
What is different about the photons from a star compared to something man-made which allows it to travel so far?

The star's bright!

Garth
 
In other words, there is nothing different about the photons themselves, it is just the sheer number of them emitted by the star.
 
Janus said:
In other words, there is nothing different about the photons themselves, it is just the sheer number of them emitted by the star.

But then doesn't that imply that photons decay? If so then, shouldn't all photons decay at the same rate? Which means that the light from stars shouldn't be visible. Sorry, I'm a noob. I googled a lot of info but it's hard for me to find accurate and very specific answers to very specific questions. I appreciate any and all replies.
 
But then doesn't that imply that photons decay?
No, they merely get http://en.wikipedia.org/wiki/Inverse-square_law" , lost in the universe.
 
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Ich said:
No, they merely get http://en.wikipedia.org/wiki/Inverse-square_law" , lost in the universe.

Is the dillution rate constant?

If not, then, would light from a flashlight have limited range because the photon dillution rate is much higher than the rate of the light from stars?
 
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I don't know how a "dilution rate" should be defined. If you take a look at the link in my last post, you see that the photons simply spread over an increasingly large area as they gain distance from the star.
 
dizam said:
Is the dillution rate constant?

If not, then, would light from a flashlight have limited range because the photon dillution rate is much higher than the rate of the light from stars?

"dilution rate" is simply a way of saying that something further away appears less bright, because there are fewer photons per unit area (or per eyeball) as the light spreads out over a larger area.

There's no difference between man made photons and natural photons. They are all just photons.

A Sun-like star appears no more and no less bright than a 3.8 x 1026 Watt light bulb.
 
To answer your initial question nothing. There is no difference between sun made photons and flashlight made photons. They are both stable (do not decay). They both travel at the same speed c. They both just keep going until they hit something. Then they may be absorbed or scattered.
 
  • #11
Photons must be stable, else the Electromagnetic force would be limited in range...(IIRC)
 
  • #12
Photons disperse and scatter, they do not become 'diluted' over time.
 
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