1. Justatruthseeker

    Justatruthseeker New Member

    [Admin: The following post argues that the inverse square law makes it impossible to see long distances (billions of light years) with a telescope, however is off by several orders of magnitude, primarily because because it neglects the effects of long exposure. See full discussion in the thread that follows this post]

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    How far do you believe the Hubble allows us to see?

    It's mirror has a surface area of 49,062.5 cm^2 the average human eye has a surface area of 0.38465 cm^2.

    In comparison with the lens of the eye it has an objective diameter of 357.14 times larger than the human eye. It's surface area is 127,551 times that of the human eye.

    This means Hubble collects 127,551 times more light than the human eye, so can make objects appear 127,551 times brighter than with the human eye.

    Now, being the inverse square law of light says that the apparent intensity of the light of a point source is inversely proportional to the square of its distance to the observer. This means that if the distance of a star is doubled its apparent light is reduced four times. If its distance is increased three times its apparent luminosity is reduced nine times. See following link for the inverse square law.

    http://hyperphysics.phy-astr.gsu.edu/hbase/vision/isql.html

    Assuming that a star is so far away that it is barely visible to the naked eye, we know that the Hubble telescope can make the star appear 127,551 times brighter. Does this mean that the Hubble telescope enables an observer to see the star if it were 127,551 times farther away? The answer is no. The Inverse Square Law says that the light that we receive from a star is inversely proportional to the square of its distance. According to this law, at that distance, the light of the star becomes 127,551^2 or 16,269,262,700 times dimmer, far too dim for us to see with the telescope.

    This raises the question: What is the maximum distance an object can be seen through the Hubble telescope? The answer is 357.14 times the distance that the naked eye can see. The reason is that an object 357.14 times farther away, its light becomes 127,551 times dimmer. Since the Hubble telescope can make a star appear 127,551 times brighter, then looking through the telescope the star would be barely visible.

    Of course this does not take into account long exposures to film or digital media which would increase the distance several times, but not the claimed billions.

    So would someone taking the inverse square law of light into effect show me how we can see galaxies a claimed 13.7 billion light years away? Remember - magnification spreads out the light received and so does not make a star appear brighter, but actually dimmer. Because this would mean the human eye can see 38,360,306 million light years????? See following link for the furthest object that the human eye can see.

    http://www.physics.ucla.edu/~huffman/m31.html



    The very math itself for the inverse square law of light debunks the claim of telescopic distances. But then that is why even professional astronomers will never discuss the inverse square law of light in connection with telescope distances. Every one I have contacted has refused to answer my question without ignoring the inverse square law.
     
    Last edited by a moderator: Jan 28, 2016
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  2. Chew

    Chew Senior Member

    "several times"?

    Nope. Look into that and you'll find the answer to your question.
     
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  3. Chew

    Chew Senior Member

    Oh, and this is mostly wrong. Higher magnification enables dimmer stars to be seen.
     
  4. Justatruthseeker

    Justatruthseeker New Member

    Yep.

    And of course you ask we ignore the inverse square law in going beyond those "several times", right?

    https://en.wikipedia.org/wiki/Inverse-square_law



    But if you have something besides a claim that it can occur, please let me know.

    Thanks
     
  5. Justatruthseeker

    Justatruthseeker New Member


    Incorrect. Magnification defeats the purpose of making an image brighter. A common misconception among the populace is that magnification helps.

    https://starizona.com/acb/basics/equip_magnification.aspx

     
  6. Balance

    Balance Senior Member

    Have you taken into account the image sensors? I'm sure they're not directly comparable to the human eye, which seems to be the basis of your query?
     
  7. Justatruthseeker

    Justatruthseeker New Member

    A telescope works on the same principle as the human eye - the ability to gather light.

    https://starizona.com/acb/basics/observing_theory.aspx



    https://en.wikipedia.org/wiki/Optical_telescope



    It is only the aperture size of the primary mirror that determines it's light gathering power. The sensors have nothing to do with how much light it can gather. The sensors only determine the upper level of resolution. Example a 4 megapixel camera verses an 8 megapixel camera. The 8 megapixel camera has finer resolution but collects no more light than the 4 megapixel camera, assuming both have the same lens size opening.
     
  8. Chew

    Chew Senior Member

    lol. The inverse square law is inapplicable to the exposure time. Nice try though.

    For an example of long exposure times, check out the Hubble Deep Field image. It is made of 342 separate stacked images taken for a minimum of 30 hours of exposure.
     
  9. Chew

    Chew Senior Member

    I must have magic eyes then. Whenever I zoom in on a star the background gets darker and the star stands out more.
     
  10. Chew

    Chew Senior Member

    Sure. But it has everything to do with how much light is stored.
     
  11. Justatruthseeker

    Justatruthseeker New Member

    Which enables it to see several times further. But each and every one of those exposure times is limited by the inverse square law. It gathers no more light in one exposure than it does in another. They are stacked on top of one another to increase DETAIL.

    A one hour exposure on Sunday gathers no more light than a one hour exposure on Tuesday.
     
  12. Justatruthseeker

    Justatruthseeker New Member

    Your eye does not magnify - you are simply focusing on one star and therefore gathering more light from that star and less from the surrounding stars. Don't confuse focusing on a star with magnification.
     
  13. Justatruthseeker

    Justatruthseeker New Member

    Which can increase the distance several times. Yet again a one hour exposure on Sunday gathers no more light than a one hour exposure on Tuesday. It just allows you to increase the resolution (DETAIL) and only increases the distance by a factor of several times - not billions. The inverse square law ALWAYS applies, that's why we call it a law.
     
  14. Justatruthseeker

    Justatruthseeker New Member

    If you are going to claim the inverse square law does not apply - you must first open a thread and debunk the inverse square law.
     
  15. Balance

    Balance Senior Member

    I understand that, and I apologise if I'm off target on what you're saying but am willing to learn
    I'm just asking if electronic/optical imagery sensors would distort your comparison to the human eye?
     
  16. Chew

    Chew Senior Member

    You thought I was referring to increasing the magnification of my eye??? Are you for real?
     
  17. Chew

    Chew Senior Member

    Do you think your eye can take a one hour exposure? Your OP compared the human eye to the Hubble.

    And the inverse square law has nothing to do with exposure time. The inverse square law only determines how many photons will enter the telescope; it tells us nothing how long those photons are collected. It is an entirely different parameter than the inverse square law.
     
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  18. Chew

    Chew Senior Member

    No, it doesn't. The diameter of your optics determines resolution.

    The distance doesn't need to be increased a billion-fold. As you said in the OP, M31 is 2 million light-years away.

    [...]
     
    Last edited by a moderator: Jan 28, 2016
  19. Mick West

    Mick West Administrator Staff Member

    The most distant galaxies are only visible with gravitational lensing, and would be invisible to the Hubble alone.
    http://www.space.com/18502-farthest-galaxy-discovery-hubble-photos.html



    Although the infrared James Webb Space Telescope apparently should be able to see things at that distance.
    http://imagine.gsfc.nasa.gov/features/cosmic/farthest_info.html
     
  20. Justatruthseeker

    Justatruthseeker New Member

    The optical sensors simply affect the detail that can be attained. And all fall far short of the human eye.

    http://www.cambridgeincolour.com/tutorials/cameras-vs-human-eye.htm



    https://answers.yahoo.com/question/index?qid=20090207234120AAvedWz



    Your camera sees nothing your eyes do not see. If the CCD affected what you see then cameras would not take the same image our eyes see.

    So in reality the Hubble has less resolution of detail than is capable by the human eye. But again - resolution of detail has nothing to do with it's ability to collect and gather light which is determined solely by its aperture and the inverse square law of light. As stated it would only increase the distance several times, because each exposure is limited in distance by the inverse square law. Multiple exposures do not enable it to see the billions of light years that is claimed. A point source would have to be metaphysical in brightness to attain the distances claimed by modern cosmology since the intensity of the light is proportional to the square of the distance.

    That is - the sun at 3 times the distance would be nine times dimmer.

    Since further galaxies are claimed to be young - they should therefore have less stars and be less bright - not increase in brightness which would be required under current belief in distances of telescopes. This is why metaphysical processes are declared for those further galaxies, because in order to be seen at the distances claimed - they would have to have a light source beyond anything even imagined.

    Distances are calculated by cosmological redshift - which is the biggest blunder in all of modern cosmology.

    http://www.newtonphysics.on.ca/hubble/

     
  21. Mick West

    Mick West Administrator Staff Member

    The effective exposure time of the human eye is under 0.1 seconds (try opening and closing your eyes within 0.1 seconds, you can still see stars). The longest Hubble UDF exposure was effectively ~350,000 seconds. So the exposure multiplication is (conservatively) 3.5 million.

    So if we accept the OPs figure of 127,551, that means the Hubble gets 450 billion times as much light as the human eye during the combined exposure.
     
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  22. Justatruthseeker

    Justatruthseeker New Member

    And at 6 million light years away would be nine times dimmer.

    [...]
     
    Last edited by a moderator: Jan 28, 2016
  23. Justatruthseeker

    Justatruthseeker New Member

    And the inverse square law does not allow it to see any further than 357.14 times the distance of the human eye, because at 357.14 times the distance the light is 127,551^2 or 16,269,262,700 times dimmer, far too dim for us to see with the telescope.

    [off topic material removed]
     
    Last edited by a moderator: Jan 28, 2016
  24. Mick West

    Mick West Administrator Staff Member

    With inverse square, the fraction of light (F) of an object at distance Dmax relative to the max distance we can see by eye (Deye). We know long exposure Hubble can see something with 1/(450 billion) times the light.

    F = (Dmax/Deye)^2 (inverse square law)

    Hence
    Dmax = Deye*Sqrt(F)
    Dmax = Deye * Sqrt(450,000,000,000)
    Dmax = Deye * 670,820

    Which is considerable more than 357. So please address that before proceeding.
     
  25. Justatruthseeker

    Justatruthseeker New Member

    In comparison with the lens of the eye it has an objective diameter of 357.14 times larger than the human eye. It's surface area is 127,551 times that of the human eye.

    http://www.physics.ucla.edu/~huffman/m31.html



    Go ahead, plug that two million light years into your equation.

    [...]
     
  26. Chew

    Chew Senior Member

    Your belief that those are the only two factors is apparently unshakable. Good luck with that.
     
  27. Mick West

    Mick West Administrator Staff Member

    Dmax = Deye * 670,820

    Dmax = 2 million light years * 670,820 = ~1.2 trillion light years.
     
  28. Justatruthseeker

    Justatruthseeker New Member

    Oh there is also dust extinction, but it seems that is to be ignored since it's off topic somehow in a discussion about telescopic distances.
     
  29. Justatruthseeker

    Justatruthseeker New Member

    Whats F, since that's the fraction of light we can see at Dmax, but you can't know that without assumption.

    Since Dmax = Deye*Sqrt(F) you must first deduce F. But since F relies on DMax, your assuming quite a few parameters without proving any of them.
     
  30. Chew

    Chew Senior Member

    From the same website you quoted earlier:

    https://starizona.com/acb/ccd/projectsfaint.aspx
     
  31. Mick West

    Mick West Administrator Staff Member

    F was calculated earlier as 450 billion by multiplying the incident light area scale (127,551) by the exposure time scale (3.5 million)

     
  32. Mick West

    Mick West Administrator Staff Member

    We know F for the specific situation we are talking about (the Hubble), as we know the relative size of the mirror and exposure time, so we can use F and Deye to calculate Dmax.
     
  33. Mick West

    Mick West Administrator Staff Member

    And if a Dmax of 1.2 trillion light years seems rather large, as the universe is only 13 billion, remember that the distant objects are generally (relatively) very small. The Andromeda galaxy is 220,000 light years across, but the farther object, MACS0647-JD, is only 600 light years across.

    So Dmax in that equation above is the maximum distant that andromeda would be visible. You'd ned to scale that by the relative brightness of the object.
     
  34. Justatruthseeker

    Justatruthseeker New Member

    The 127,551 already includes the calculation of light gathered by the mirror. Exposure time does not increase that amount of light given because you must first also apply the inverse square law to any distance. At 357.14 times the distance of the human eye the light is 127,551^2 or 16,269,262,700 times dimmer. You can't multiply exposure time by the light collected by the amount of light gathered. It doesn't work that way. You are violating the inverse square law. The same point source 357.14 times the distance of the human eye becomes 127,551^2 or 16,269,262,700 times dimmer. All you can do is multiply that 2 million by 357.14 (the difference in the objective diameter of the telescope compared to the human eye).

    This gives you 714,280,000 light years max. No this does not account for long exposures which increase it several times, but you cant support billions. You know this as well as I do. You can't ignore objective diameter which is 357.14 times that of the eye allowing it to collect 127,551 times more light at 2 million light years. Exposure time does not increase the objective diameter nor the surface area. Nor does it increase the distance except to make fainter objects brighter.

    Then you clipped the part of dust extinction because you knew it shattered your beliefs and you had no work around to that problem. Your only solution was to clip dust extinction from the debate and claim it is off-topic in a topic about astronomical viewing range - of which dust extinction is paramount.

    All I am getting from this is you will declare whatever you can't answer as off-topic to avoid having to deal with it.
     
  35. Mick West

    Mick West Administrator Staff Member

    yes it does, more time = more photons.

    The inverse square law says an object that is X times as far away as another object will require X^2 as much light to be equally visible.


    So, for 13 billion vs 2 million, you need (13,000)^2, or 169,000,000 times as much light.

    You can do that with a 127,000x larger area (mirror vs. eye) and a 1330 times longer exposure. All quite possible with the Hubble.

    [Edit: Correction for value of 13 billion / 2 million]
    So, for 13 billion vs 2 million, you need (6,500)^2, or 42,250,000 times as much light.

    You can do that with a 127,000x larger area (mirror vs. eye) and a 332 times longer exposure. All quite possible with the Hubble.

     
    Last edited: Jan 28, 2016
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  36. Mick West

    Mick West Administrator Staff Member

    Dust is irrelevant in the calculation of Dmax, because it's a linear factor that is already included in the Andromeda observation.
     
  37. Mick West

    Mick West Administrator Staff Member

    I think the root misunderstanding here is that you don't understand how longer exposure can make a distant object visible.

    Would you agree though that a ten second exposure of the sky at night would show a lot more stars than a 1/10th second exposure. All other things being equal?
     
  38. Justatruthseeker

    Justatruthseeker New Member


    More photons that still obey the inverse square law.

    But Hubble does not have a mirror 127,000x larger, but only 357.14 times as large. It's objective diameter is only 357.14 times that of the eye, not 127,000 times larger.

    No because at 13 billion the light would be (13,000,000,000)^2 not 13,000^2 or 1.69x10^20th dimmer
     
  39. Justatruthseeker

    Justatruthseeker New Member

    It would increase the amount of stars visible, but not the distance that those stars could be seen by any drastic measurement. It would make the fainter ones more visible but not by any measurement of just a few parsecs, if that.

    And we have yet to add light extinction into the equation by dust, which is 30 times more abundant then previously believed.
     
  40. Mick West

    Mick West Administrator Staff Member

    But we are calculating the relative brightness of things at 13 billion and 2 million, not 13 billion and 1.

    I made a mistake above, the relative brightness would be
    (13,000,000,000/2,000,000)^2
    or 6500^2, hence 42 million times dimmer

    You understand this? 13 billion light years is only 6500x times as far away as 2 million light years. Right?

    So if something is 6500x as far way, it would be 42,250,000 times dimmer, right?

    So to see it, you just need to get 42,250,000 as much light onto the sensor, right?
     
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