Thunderbolts Forum v3.0

Higsy:

Your figures are wrong.

Those are not my figures, those are from the authors of the paper on 'Orbital imagery for planetary exploration'. I am asking what the measured values are, not theoretical ones base on assumptions. It was a trick question really as there are no actual measured values I can find, except one, which was of the Earth from half way to the Moon with a spot meter reading of 320 lumens.
https://youtu.be/x1F4ujSA9Rc?t=528
Does that seem right by your reckoning Higsy?
Its puzzling to me why the light levels on the lunar surface are not well studied. If there are going to be colonies or maybe mining operation on the surface then surely they need to know some basic figures. On the near side it will never be totally dark at night due to Earthshine and NASA determined it would be bright enough for the astronauts to safely conduct their experiments. We can see well enough under a full moon to perform many tasks, and according to NASA Earthshine provides 75 times more photons than does the full moon on Earth so it should be easily possible to work though the lunar nearside night.
What about the other extreme? At mid day on the near side will they need the dark visors or Neutral density filter glasses. Just how bright is it at mid day?
Why don't we know?? And what about the far side? We have no clue whatsoever, though I'd expect the Chinese to have taken a light meter, or knowing the camera specifications and exposure times could work it out.

The neutral density (ND) filter is one of those tools that should be in almost every photographer’s camera bag.

https://www.bhphotovideo.com/explora/ph ... ty-filters
But NASA doesn't need them on a blindingly bright lunar surface, or to take photos of the Sun from space? Harumph.

GaryN wrote: ↑Sat Nov 28, 2020 6:19 pm What about the other extreme? At mid day on the near side will they need the dark visors or Neutral density filter glasses. Just how bright is it at mid day?

About the same as on Earth, or somewhat less because of the low albedo.

Why don't we know?? And what about the far side? We have no clue whatsoever, though I'd expect the Chinese to have taken a light meter, or knowing the camera specifications and exposure times could work it out.

Thousands of photos have been taken of the Moon and planets with known optical systems and sensors. Why don't you work it out? I don't know of any anomalies and you haven't produced any.

The neutral density (ND) filter is one of those tools that should be in almost every photographer’s camera bag.

https://www.bhphotovideo.com/explora/ph ... ty-filters
But NASA doesn't need them on a blindingly bright lunar surface, or to take photos of the Sun from space? Harumph.

[/quote]What makes you think the lunar surface is blindingly bright?

Thousands of photos have been taken of the Moon and planets with known optical systems and sensors. Why don't you work it out?

I tried but gave up, the task is above my pay grade. I have not found anyone who could succeed, my only hope is that your obviously superior intellect can.

I don't know of any anomalies and you haven't produced any.

Surely the fact we have no actual measured surface illumination levels for any of the planets is an anomaly? To a suspicious observer it might seem there is something amiss.

GaryN wrote: ↑Sun Nov 29, 2020 9:26 pm

Thousands of photos have been taken of the Moon and planets with known optical systems and sensors. Why don't you work it out?

I tried but gave up, the task is above my pay grade. I have not found anyone who could succeed, my only hope is that your obviously superior intellect can.

I did a few calculations based on the published camera systems on planetary and lunar robotic missions up the thread. That should give you a starting point.

I don't know of any anomalies and you haven't produced any.

Surely the fact we have no actual measured surface illumination levels for any of the planets is an anomaly? To a suspicious observer it might seem there is something amiss.

To a paranoid observer mired in conspiracy theory it might; to the rest of us, not so much. We have measured the Sun's output up the wazoo inside and outside Earth's atmosphere. Allowing for known atmospheric effects the two kinds of measurement match perfectly. Simple geometric radiometry tells us how the Sun's irradiance and illuminance changes with distance, so we know what those values are at the various planets. The luminance of those planets has been measured inside and outside the atmosphere (every astronomer knows what the luminance of each planet is) so we can derive the overall albedo. The surface scene brightness then depends on several things such as local albedo and photometric function, local angle of Sun's illumination and the angle between the illumination and the viewing direction. The cameras on all the missions were designed using these considerations and they all worked. So why would anyone think there's a problem. And why would any of the space organisations in the different countries waste valuable resources and mission time testing something that is so predictable and well understood, when there is so much to discover that we don't already know.

It's so Dark, Bennu.
https://www.sciencedirect.com/science/a ... 3520304759

Look at the exposure times and normal albedo. But, this is just an amazing achievement all around. Such clear and high definition of an asteroid, stunning.

We have measured the Sun's output up the wazoo inside and outside Earth's atmosphere.

From outside of Earths atmosphere the heat of the Sun has not been measured directly, you know that. The spectra have been measured and the Sun ASSUMED to be a blackbody, but nobody has proved it is. As a scientist I will not accept assumptions when the necessary scientific experiments are cheap and simple to perform. Prove to me that the Sun is a blackbody or show, with your calculations, using Mercury Messenger data the value of the Sun lit surface illumination level of Mercury or you are on my ignore list.

GaryN wrote: ↑Tue Dec 01, 2020 7:41 pm

We have measured the Sun's output up the wazoo inside and outside Earth's atmosphere.

From outside of Earths atmosphere the heat of the Sun has not been measured directly, you know that.

The Sun's absolute spectrum has been measured from radio frequencies to gamma rays. That is all there is to the Sun's radiation (apart from polarisation). There is no separate "heat" to measure. That is what I know.

The spectra have been measured and the Sun ASSUMED to be a blackbody, but nobody has proved it is.

Who has claimed that the Sun is a blackbody? Not I nor anyone I respect. I have said the Sun's spectrum is a near blackbody spectrum, but that is a matter of observation not assumption.

As a scientist I will not accept assumptions when the necessary scientific experiments are cheap and simple to perform.

Nor should you. As a scientist, do you understand what the statement "the Sun's spectrum is measured to be near blackbody" means?

Prove to me that the Sun is a blackbody or show, with your calculations, using Mercury Messenger data the value of the Sun lit surface illumination level of Mercury or you are on my ignore list.

My dear fellow, so cruel?

Higgs, if you haven't ignored me by now. Go and Google Image Search lunar samples nasa archives. And look for pictures of the same rock, and the different exposures/light-balance applied. You can find a few that are 'natural' but most are 'over-exposed' to make the rock look 'brighter' then it actually is. There is one in a I saw, multiple publications, a pile of rocks in a stainless steel tub, in one it's normal, in the rest they are over-exposed to make them less 'dark'.
And for most of the published photos, notice the white-balance. It's very very high. The Moon is predominantly very dark material.

Cargo wrote: ↑Thu Dec 03, 2020 6:08 am Higgs, if you haven't ignored me by now.

My dear chap, why should I ignore you?

Go and Google Image Search lunar samples nasa archives. And look for pictures of the same rock, and the different exposures/light-balance applied. You can find a few that are 'natural' but most are 'over-exposed' to make the rock look 'brighter' then it actually is.

What do "natural", "over-exposed" and "brighter" actually mean in this context?

There is one in a I saw, multiple publications, a pile of rocks in a stainless steel tub, in one it's normal, in the rest they are over-exposed to make them less 'dark'.

How do you know that they are "over-exposed"?

And for most of the published photos, notice the white-balance. It's very very high.

What do you mean by a "very very high white balance"? I don't think the term white balance means what you think it means.

The Moon is predominantly very dark material.

That might well be so, and indeed the Sun's albedo is low compared to other planets and moons in the solar system (though not the lowest), but what has that to do with the discussion in this thread, which is about whether the Sun emits visible light. Which, of course, it does.

Well, you have missed so many of points and questions, I was simply beginning to wonder.
Sorry about term salad, I reverted to basic human photographer street words. So unscientific you would probably say. You could try and look for the pictures yourself.

Here's the dark pinch, it's not whether [or not] the Sun (and Stars) emit visible light wavelengths, it's 'how much', and the evidence says, not very much. Maybe .1%-2% of it's power is visible, would not surprise me. The "Solar Wind" certainly is not visible, is it?

Can you get a picture like these from the dark side of the moon?
https://www.google.com/search?q=milky+w ... from+earth

Cargo wrote: ↑Fri Dec 04, 2020 6:01 am
Here's the dark pinch, it's not whether [or not] the Sun (and Stars) emit visible light wavelengths, it's 'how much', and the evidence says, not very much.

Well perhaps you can present that evidence here, because as sure as eggs is eggs, GaryN has failed to do so.

Maybe .1%-2% of it's power is visible, would not surprise me.

Evidence?

The "Solar Wind" certainly is not visible, is it?

What has the "visibility" of the solar wind to do with the stellar/solar radiation?

Black is the darkest color, the result of the absence or complete absorption of visible light.

So if the Sun emits no visible light then it is black, and the Sun is by definition a body, so therefore in one respect it is a black body. Planet Mercury they tell us has a very dark surface that absorbs over 90% of the visible light from the Sun, which is why its surface is so hot. It reflects less than 10% of the visible light and radiates the rest away at infrared wavelengths. So Mercury is a blackbody and also a black body! The are no visible light photos of Mercury from outside of Earths atmosphere or from orbit around Mercury, they are all in the IR.

Mercury, the smallest and closest to the sun has no atmosphere and extremes of temperature that average to about that predicted by our simple black body model.

https://www.acs.org/content/acs/en/clim ... tures.html

The measured surface temperature of Mercury however could be and most likely is produced not by the heat coming from the Sun, which has never been proven by empirical scientific methods, but by electron orbital transition heating of the surface materials. We have no photos of the Sun from the surface of Mercury, just as we have no photos of the Sun from cislunar space, only artists impressions. And the Sun is white seen from space, so they say. Someone should tell the artists.
http://www.astronoo.com/images/enfants/ ... ercure.jpg
If the Goddard Planetary Systems Laboratary can provide me with no actual measured surface illumination levels for the Moon, Mercury or Mars then nobody can, and there are only values based on that clearly obsolete solar constant model, while the untested ALT model would be found to be the correct one, or much closer at least.

The Sun is not what we are told it is. Sure we can detect by way of some complex instruments and a lot of math much of what is happening in the outer layers but what is at the core is not understood by modern science, and the real nature of the Sun will never be understood by conventional scientists, only the spiritual ones.
Cargo:

Can you get a picture like these from the dark side of the moon?

Not from the near or far side, or from cislunar space. Ever.

GaryN wrote: ↑Fri Dec 04, 2020 7:47 pm

Black is the darkest color, the result of the absence or complete absorption of visible light.

The are no visible light photos of Mercury from outside of Earths atmosphere or from orbit around Mercury, they are all in the IR.

That is a false statement. I told you in this thread about photographs of Mercury's surface taken in the visible. Why are you lying again?

The measured surface temperature of Mercury however could be and most likely is produced not by the heat coming from the Sun, which has never been proven by empirical scientific methods...

That is a false statement. The entire spectrum of the Sun has been measured over and over again. I explained that more than once in this thread. Why are you lying again?

but by electron orbital transition heating of the surface materials.

What?

...clearly obsolete solar constant model...

Clearly obsolete? Why do you say that? Evidence?

So I did find a mention of the light meter being used during the Apollo 8 mission from orbit. Here is a view of crater Aitken taken from Apollo 8 using the 250mm lens and the 3400 film. The 3400 also was an extended red film, medium speed.
https://www.lpi.usra.edu/resources/apol ... 08-13-2322

075:23:51 Anders (onboard): And was taken at 1/60th of a second at 5.6 with the terminator. We'll do it at 250th - that's good enough.
075:24:13 Anders (onboard): Spotmeter readings vertically are recorded on the map for lumens...
075:24:27 Anders (onboard): And they're all reading between 160 and 320.
075:24:36 Anders (onboard): Oblique: about 4 in the - between 460 and 320.

Here is a view of Aitken from the far side showing that it would have been lit entirely by Sunlight, no Earthshine. X marks the spot. I have not yet found a spot meter reading for the Sun and Earthshine lit near side.
(I can not link to the image but if you copy and paste it does show. Time for a new BBS I think.)
www3.telus.net/myworld/A8Aitken.png

I see what I did wrong, I did not include the http://
http://www3.telus.net/myworld/A8Aitken.png

So given the Moons albedo and the 120-130,000 lumens value of Sunlight (measured at the top of Earths atmosphere) then a simple model would show that the lunar surface illumination of Aiken is far below what would be expected. The near-IR would seem to be strong, so it would make sense that the Apollo astronauts 'dark' visors were primarily IR blockers which did not attenuate the visible wavelengths much at all. Certain IR wavelengths can be damaging to the eye, cataracts being the main concern.
As the Apollo astronauts all commented, lighting on the Moon is very strange, and a comprehensive scientific study of those conditions would no doubt lead to some very uncomfortable questions being directed at NASA. No wonder they have been foot-dragging on a return to the Moon for over 50 years.