Why Isn’t the Night Sky Full of Light from All the Galaxies?

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Discussion Overview

The discussion revolves around the question of why the night sky is not filled with light from the numerous galaxies in the universe. Participants explore various aspects of this phenomenon, touching on theoretical implications and observational limitations.

Discussion Character

  • Debate/contested

Main Points Raised

  • Some participants suggest that the sheer number of galaxies should result in a brighter night sky, questioning why this is not observed.
  • Others reference "Olber's paradox" as a potential explanation for the observed darkness of the night sky.
  • One participant notes that the number of galaxies does not change during the day, yet the sky is bright due to the sun's light scattering in the atmosphere.
  • Another participant argues that the number of galaxies alone may not be the only factor influencing the visibility of light in the night sky.
  • It is mentioned that the number of galaxies visible from Earth is finite, and even the brightest galaxies beyond the Milky Way are challenging to see with the naked eye.

Areas of Agreement / Disagreement

Participants express differing views on the factors contributing to the darkness of the night sky, with no consensus reached on a definitive explanation.

Contextual Notes

Some assumptions regarding visibility, distance, and the nature of light from galaxies remain unaddressed, and the discussion does not resolve the complexities of Olber's paradox.

adjacent
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If there are so many galaxies in the universe,Why don't wee see a night sky with full of light(from the galaxies or stars)
 
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adjacent said:
If there are so many galaxies in the universe,Why don't wee see a night sky with full of light(from the galaxies or stars)

Google "Olber's paradox"
 
adjacent said:
If there are so many galaxies in the universe,Why don't wee see a night sky with full of light(from the galaxies or stars)

During the day the number of galaxies doesn't change and we see the sky full of light.
 
martinbn said:
During the day the number of galaxies doesn't change and we see the sky full of light.
Night sky Martinbn
 
I know, I am just pointing out that may be it is not only the number of galaxies that matters.
 
During the day we see sky full of light because of sun's scattered light on our atmosphere
 
This thread is becoming absurd. The answer to the original question is

Google "Olber's paradox"
 
thanks
 
The number of galaxies viewable from Earth is finite, and even the brightest galaxy [beyond the milky way] is difficult to see with the naked eye.
 

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