Simply answer the very straight forward question about space ,
What is the INTENSITY of starlight whitout the use of optics, viewed from the daylight side of the moon and (cis)lunar space without looking directly towards the sun?
I could give an to that question that you asked, but it would probably would be useless information for what you want to know.
"The INTENSITY of starlight" is incredibly small compared to sunlight. For example:
Illuminance Example
120,000 lux Brightest sunlight
0.25 lux Full Moon on a clear night
0.0002 lux Starlight clear moonless night sky excluding airglow (similar to on moon)
From: Wikipedia, Daylight
These are
on earth, but in space there us little difference, except for
airglow, which has been excluded.
The reason I claimed that these were useless,is these would indicate what exposure would be needed to photograph a scene illuminated by sunlight, moonlight or starlight.
It is, more or less, what you asked for, but I guess what you need to know is the exposure needed to photograph the stars and how visible stars would be to the unaided eye.
Again, I can't give you details of what might happen in space, but in fact, the atmosphere does not diminish sunlight or starlight very much. What does happen is that the scattering of light by the atmosphere completely overpowers the very faint starlight.
This of course does not happen in space as the exposure for datlight.What might come closer to answering your question is the exposure needed to
photograph a sunlit scene and to
photograph the stars themselves.
This information is readily available from photography websites. Here is a typical photo of the night sky:
This is all very approximate, but in bright sunlight a typical exposure might be for an ISO of 200 at
1/200th of a sec, f16.
At this f.stop and exposure stars would be so underexposed that they would be totally invisible.
The exposure for the stars lets in roughly 30,000 times as much light!
This has been with a camera, but what about a person's unaided eye?
What is certain is that the unaided eye can see clearly in bright sunlight and see the stars at night, but considerable time is needed for the eye to
adapt to the darkness. See
How long does it take our eyes to fully adapt to darkness? Human eyes take several hours to fully adapt to darkness and reach their optimal sensitivity to low light conditions. The quickest gains in vision sensitivity are made in the first few minutes after exposure to darkness. For this reason, many people think that after only a few minutes, their eyes have reached their peak sensitivity. But several hours into darkness exposure, the human eyes continue to adapt and make small gains in sensitivity.
More information in: How long does it take our eyes to fully adapt to darkness?
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A rule-of-thumb for ship's lookouts is that around 20 minutes is needed to adapt to dark conditions, though 10 minutes would be adequate to see stars clearly enough.
with the above criterea as reference.......
stars are not visible without the use of optics
stars are visible without the use of optics, but our eyes need to adjust
stars are immediatly visible but less bright than an earth's avarage nightsky
stars are of the same intensity compared to an avarage nightsky on earth
stars are more intense because of the absent atmosphere
stars are so bright it causes an almost religious experience
other
Of course, I have never experienced "stars in space", but from what I know and what I have read, I would expect thst:
The stars would be easily visible and a little brighter than on earth, but the absence of
sky-glow would make the background completely black, making the contrast much more intense.
The two situations (standing on the daylight side of the moon and traveling in deep space, both without directly looking towards the sun and without the use of optics or other equipment) should have a straight forward answer.
On the sunlit lunar surface, I would expect that the stars would be quite invisible to the unaided eye, unless steps were taken to give time to adapt, and to avoid exposure to bright objects.
When it comes to photographs, if the exposure were set for the brightly lit lunar surface star's would be quite invisible.
A camera's exposure setting can be changed much more quickly than the eye takes to adapt and some of the Hasselblad cameras used on the moon might have handled it, but the scene would have to include no bright lunar surface.
There is one other point, but I have no idea of it's significance. The moon does have a very slight "dusty haze" over it from charged particles repelled from the surface by the slightly positively charged surface. This is probably too slight to affect either the view of photography.
The same would apply if travelling in deep space, except that it might be easier to avoid looking at sunlit objects.
Is this THE most difficult question ever ? It seems to be the case, because all of you refuse to answer awhat should be much less complicated than rocket science !
No big problem with a bit of background in photography and in the way the human eye works.
Please !!!!!!!!!! Would you give it your best shot now ?
Well, that's my "best shot". I have never been ti space and you are only guessing.
But I would say that I find no inconsistency in one person saying that they did not see stars on the moon's surface and someone else saying that is possible to see stars in the space around the moon - it all depends!