Average luminosity of night sky vs frequency

In summary, the average luminosity of the night sky is relatively low, and there is no survey that can provide an estimate of average luminosity plotted against wavelength.
  • #1
turbo
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Average luminosity of night sky vs frequency...

What is the average luminosity of the night sky in all observable wavelengths, from the shortest down to the longest? Are there estimations/approximations anywhere of average luminosity plotted against wavelength? Are there links to papers that anyone can offer? The common words that I use to Google this question give far too many results, almost entirely irrelevant.

The reason I ask this is an interest in "tired light". If cosmological redshift is not a function of universal expansion, and is instead a function of the interaction of EM with the fields through which it propagates (yes, I'm still modeling those pesky ZPE fields!) we should expect that a static infinite universe will have an almost isotropic luminosity at the very longest wavelengths. The absence of isotropy at the longest wavelengths would falsify, or at least seriously constrain a tired-light model in an infinite universe. What's more, if redshift by ZPE field interaction is wavelength-dependent (energetic, short-wave EM interacts more strongly and is redshifted more than longer wavelengths), there should be a discernable rise in luminosity as wavelengths increase, since longer wavelengths will be "selected for" by the mechanism of interaction. I envision an Olber's paradox type effect, in which the background of the universe might be quite luminous, but at VERY long wavelengths.
 
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  • #3
I thank you for the link, my friend, and frequent advisary. :smile: The request, however, was for a link to a surveyed averaged luminosity related to wavelength. Olber's paradox has been cited many times, and there are lots of interpretations of how it should be dealt with, but I would like to know if there has been an all-sky survey made at VERY low frequencies that could falsify or support my ideas.
 
  • #4
  • #5
I did some more digging on this. I thought I found just what you are looking for, but, the crucial plot of the full spectrum data is missing! That was very irritating:

Diffuse Background Radiation
http://arxiv.org/abs/astro-ph/9903294

So, I dug up some other sources of data ranging from visible to long wavelengths. Hopefully you will find it... illuminating:

The First Detections of the Extragalactic Background Light at 3000, 5500, and 8000A (I): Results
http://arxiv.org/abs/astro-ph/0112153

The Far Infrared and Submillimeter Diffuse Extragalactic Background
http://arxiv.org/abs/astro-ph/0105550

Interferometric Observations of the Cosmic Microwave Background Radiation
http://arxiv.org/abs/astro-ph/0306383
 
  • #6
Thank you for the links. Rampaging through CiteBase yields this paper, which might be the closest thing to what I am looking for.

http://citebase.eprints.org/cgi-bin/citations?id=oai%3AarXiv%2Eorg%3Aastro%2Dph%2F0407207

The paper is written from the perspective of the concordance model, and that involves quite a number of assumptions, like the inevitability of dark matter, dark energy, etc, and the underlying assumption that distant objects are redshifted simply because the universe is expanding. I would dearly love to see a similar survey paper written by someone willing to collect and cite the observations and THEN try to derive the causes underlying the results. That would seem to me to be the proper flow of a scientific survey, but heck, what do I know?

I have been tinkering with this concept (redshifting EM into indetectability) using electricity as a model. (I fix old tube-driven guitar amplifiers as a hobby, and after I get them healthy, I punish them with my playing!) Anyway, we measure AC current as an oscillating signal around a center point (in the U.S. we call it Neutral, which is routinely tied to Ground). If we slow the frequency of the oscillation, though, the AC signal becomes almost undectable from DC. In other words, as the oscillation slows, if you do not keep your meter on the source for a long enough period of time, the very-slowly oscillating AC electricity cannot be differentiated from DC. A very-slowly oscillating signal from multiple sources (think about the virtual-particle-pairs of ZPE) would be entirely undetectable to us.

This is a problem when we extend this principal to redshifted EM, because there is no "outside the universe" ground state by which to gauge the ground state inside our universe. In this way a very large "ground state" of energy fluctuating VERY slowly would be undetectable by us, especially if the fluctuations were from a multiple number (we should reasonably say "practically infinite number") of sources that null each other. The energy level could be huge, but with no "outside our universe" ground state to compare it to, we would not be able to sense it, even if it was coordinated, which concept I would vehemently reject, in any case. Background EM that is redshifted to very long wavelengths would be indetectable to us, regardless of signal strength (total luminosity).

I have been working to parallel this with the concept that the energy of the quantum vacuum (ZPE) is theoretically 120 OOM too large to be responsible for the BB's cosmological constant. I personally do not believe (and Chronos is VERY well aware of this! :smile:) that we even need a cosmological constant, but we have to come to terms with the potential gravitational effects of a large quantum vacuum energy. I believe that this low-frequency, large-wavelength, and diffuse model of ZPE virtual-pair energy will negate the need for a highly-gravitational vacuum energy. In my present model, the vacuum fields only contribute to gravitation when they are polarized by the presence of mass. The Athena project may eventually discern an infall-rate differential between uncharged matter and antimatter, and that will very quickly validate the polarized-ZPE model of gravitation (or falsify it just as quickly, if there is no differential).
 
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Related to Average luminosity of night sky vs frequency

What is the average luminosity of the night sky?

The average luminosity of the night sky varies depending on factors such as light pollution, moon phase, and location. In rural areas with minimal light pollution, the average luminosity is around 21.6 magnitudes per square arcsecond. However, in urban areas with high light pollution, the average luminosity can be as high as 18 magnitudes per square arcsecond.

How does the average luminosity of the night sky change with frequency?

The average luminosity of the night sky does not significantly change with frequency. However, at higher frequencies, such as in the ultraviolet and infrared regions, there is more noise and interference from other sources, resulting in a lower perceived luminosity.

What factors affect the average luminosity of the night sky?

The average luminosity of the night sky is affected by factors such as light pollution, moon phase, atmospheric conditions, and the presence of other sources of light. Light pollution from cities and other human activities can significantly increase the average luminosity, while a new moon or clear sky can decrease it.

How is the average luminosity of the night sky measured?

The average luminosity of the night sky is typically measured in magnitudes per square arcsecond, which is a measure of the brightness of a celestial object over a specific area of the sky. Astronomers use specialized instruments, such as photometers, to measure the luminosity of the night sky at different frequencies.

Why is understanding the average luminosity of the night sky important?

Understanding the average luminosity of the night sky is crucial for astronomers and other scientists who study celestial objects. It helps them distinguish between natural sources of light, such as stars and galaxies, and artificial sources of light, such as cities and satellites. It also allows them to study the effects of light pollution and other factors on our view of the night sky.

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