If you read the original question by Bill and the first post in this thread by Bobby O, they are not asking for the explanation to Olbers’s Paradox. They were not expecting to see a sky so dense with stars that you can’t see gaps… Olbers’s Paradox. They want to know, given that the density of stars is basically as it appears, why don’t the individual pinpoint stars don’t flood the sky with light like billions of massive floodlights.
The original question was:
I’m enclosing an article that poses a question that had never occurred to me before: Why is the night sky dark? According to the author of the article, Robert Cowen, “the traditional answer holds that the universe is expanding so fast that light from the distant stars is degraded and thinly spread.” Another theory suggests, “the darkness is better explained by the simple fact that the universe is of finite age. Galaxies have not had time to flood the sky with starlight.” Excuse me, but aren’t we overlooking the obvious here? --Bill, Nanaimo, British Columbia
The explanations given in this question are regarding Olber’s Paradox. I didn’t follow Bill’s question about the obvious, but apparently you did. I guess that was in regards to seeing the stars with the distribution they have, etc.
JoeyBlades: In essence, Bobby O’s assessment is correct, for this question.
After your interpretation, yes. From my understanding of the original, Olber’s paradox was the question.
Bobby O: I assumed that since the sun is relatively close, and we can look at it without much interference, it doesnt need to reflect off of anything to see. We can see the stars, too, by looking at them. I thought the question was, “Why is the night sky dark?” not “Why can’t we see the stars?”
Bobby, your interpretation is a bit backwards. Stars are light emission sources, and thus much easier to see than planets, asteroids, moons, and dust that are light reflectors. Easiest demonstration - look up at night and count the visible stars. Then count the visible extra-solar planets. Hint: 0.
pldennison: Headlights also have reflectors placed behind them so that ALL the rays )for all practical purposes) exit the headlamp parallel to each other and in the same direction. Stars are spherical and give off approximately equal luminosity in all directions.
Not really parallel, but all pointing in the same general direction. However, the light from stars travels far enough before it gets here that the light rays are essentially coherent - all aligned in parallel rays. This is process that is emulated to make laser coherent. They use tubes with mirrors to simulate a long travel distance to let only the coherent light out.