The Dark Moon

Beyond the boundaries of established science an avalanche of exotic ideas compete for our attention. Experts tell us that these ideas should not be permitted to take up the time of working scientists, and for the most part they are surely correct. But what about the gems in the rubble pile? By what ground-rules might we bring extraordinary new possibilities to light?
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GaryN
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The Dark Moon

Unread post by GaryN » Thu May 21, 2020 8:29 pm

This thread is a spinoff from the Boring Sun on the old forum, in which I tried to show that once outside of Earths atmosphere the lighting, illumination and vision conditions are very different from the conditions we have been lead to believe exist out there. The experiments required to show scientifically just how different those conditions are have not been performed and are not likely to ever be.
One of the observations that puzzled me was concerning our Moon, and the fact that it can be seen sometimes during the day against a bright blue sky:
(Sorry, no pretty pictures anymore)
http://eyesonthesky.com/Blog/tabid/80/E ... -Moon.aspx
How bright is the blue sky? Depending on the latitude of the observer and the angle of inclination, between 10,000 and 50,000 Lux seem to be the accepted values, so would it stand to reason that the Moon would need to be brighter than that to be so clearly visible during the day?
How bright is the Moon? This is the most recent article I have found, and measuring the brightness at night under ideal conditions it turns out to be very low, about 0.32 Lux.
How bright is moonlight?
https://academic.oup.com/astrogeo/artic ... 31/2938119
That figure surprised me as sometimes the full Moon seems so bright that it hurts my eyes to look at it. Figures over the years have proposed up to 3 Lux, so maybe this is not an exacting science. This document from 1971 points out that an extra source of light from the luminescence of the lunar surface by way of solar UV excitation must be considered.
Photometry of the lunar surface
http://articles.adsabs.harvard.edu/pdf/ ... ...5..265L
All measurements are of course from Earth, and it seems even the LADEE mission does not provide any figures from lunar orbit. The photographs taken by the various lunar orbiter missions including the Apollo ones do not help much in trying to determine the lunar surface illumination levels as most of the films were special order for NASA and in many cases had 'mission specific' spectral layers that we have no details of. How the films were developed and processed is also unclear.
The Apollo astronauts on the surface took no direct measurements of surface illumination. They did take a spot meter on the early missions but it was only ever used for interior photography. I have had it confirmed in an email reply from Ames Research Center that there are no measured illumination levels for the the daytime near side lunar surface.
So what about theoretical illumination levels? If we use the Solar Constant values then the lunar surface will receive the same amount of direct solar radiation that Earth does. Looking directly at the Sun the Lux values are given as between 100,000 and 200,000 Lux, so should the light falling on the Lunar surface be taken as 200,000 Lux as there is no atmosphere to dim it? Then if we use the albedo of the Lunar surface at an average of 10%, would the surface be reflecting 20,000 lux? If we used that figure and model the Lunar surface as a diffuse reflector then what figure do we obtain lunar brightness measured at Earth? As the Photometry of the lunar surface paper shows, the calculations are not so simple, so I am considering only the full moon figures.
I have calculated values by a couple of diffent methods but would be interested to hear what figures others may arrive at. In the next post i will try to show from the equipment and methods utilised by NASA that the near side lunar surface illumination levels are much darker that those arrived at by theory, and at a maximum only 300 Lux, while the far side maximum illumination is probably less than 100 Lux.
In order to change an existing paradigm you do not struggle to try and change the problematic model. You create a new model and make the old one obsolete. -Buckminster Fuller

Brent72
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Joined: Sat Oct 26, 2019 1:51 pm

Re: The Dark Moon

Unread post by Brent72 » Fri May 29, 2020 11:53 am

It's a fascinating question GaryN. How does the moon emit so much EM radiation? Are you going to post more evidence that light changes its nature when it enters Earth's atmosphere? I look forward to your next posts on this.
It also makes me wonder how we can see the rocky planets shining like stars in the night sky, when they have little atmosphere and very little reflected light? How can the red planet for example look so similar to Antares?

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GaryN
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Re: The Dark Moon

Unread post by GaryN » Sun May 31, 2020 6:45 pm

Brent72 wrote:
Fri May 29, 2020 11:53 am
It's a fascinating question GaryN. How does the moon emit so much EM radiation? Are you going to post more evidence that light changes its nature when it enters Earth's atmosphere? I look forward to your next posts on this.
It also makes me wonder how we can see the rocky planets shining like stars in the night sky, when they have little atmosphere and very little reflected light? How can the red planet for example look so similar to Antares?
Hi Brent72, yes, fascinating indeed!
There really is a dearth of photometric values for not just the Moon but Mars and Mercury. We have the Mars web cam showing us a redish atmosphere, but how bright is it? Diminutive Mercury is so dark that no visible light photos of any part of its surface can be shown and the instruments on Mercury Messenger only show the surface in IR (NAC 700–800 nm) or spectrally (WAC 395–1,040 nm). If there is an engineering camera then I see no mention of it, but even if there was it would not see the surface of Mercury as it is so dark. But how bright should the surface of Mercury be given its proximity to the Sun and its surface albedo? Again, no data. Neither Mars or Mercury should be naked eye visible from Earth so the only way they can look like they do is if it is the gamma/x-ray/UV from Mars or Mercury that are being transformed by Earths atmosphere. For the surface of Venus a figure of 14,000 lux is given, but we have no measured values from orbit so it too is probably very dull when seen from orbit, but Akatsuki told us very little about visible wavelengths.
In order to change an existing paradigm you do not struggle to try and change the problematic model. You create a new model and make the old one obsolete. -Buckminster Fuller

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