The far side during a lunar night?

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What can you tell me about what this environment would be like to work in,

Is just starlight unfiltered by atmosphere enough to see by?

Would the cold be a problem for our current space suits, or would it just reduce the cooling requirements?


Good question Kelvin, and one I'm not qualified to answer.
That said, having been outside on dark, cloud free nights, away from towns and
artificial light, it can be so dark, that you cannot clearly see your feet and the
ground you stand on. Your hand can be seen infront of your face, but it has no colour.
Of course, it is not truly dark on the Earth, sky glow is usually present. Even the brighter planets,
Venus and Jupiter contribute substantial light, and at times (at least here in Australia), the
Milky Way intrudes on your night vision. Infrared night goggles can make the night scene look like day,
but in the middle of a farside night, when the terrain has reached a frigid equilibrium, even IR detectors
(at ground level) will have their limitations.
Like yourself, I can only imagine. You will need a torch :) It will be a dangerous place to be. Lunar regolith
is in the main, coal black. As black (almost) as the shadows cast by your torch - very tricky to navigate.
I don't know enough about the properties of current spacesuits subjected to a long cold soak, but
insulation from the cold would not be a problem. A vacuum is not a good conductor of .......anything, so oddly
enough, the suits may still require an evaporator system to shed excess body heat.
Would be one hell of a trip, a visit to the Land of Weird and well worth the look.


Thanks freya,

Im just trying to build up some imagery. As you say you would need a torch, and that would exclude any possiblity of your eyes adapting to natural light. I think the Tsiolkovskiy crater has about the same declination as the galactic centre so you would get a great view of the milky way on some dates. (though I didnt know what declination was till I looked it up :) ) One advantage of torchlight could be a better sense of depth. Getting lost or turned around could be quite a risk. I imagine rovers with very tall antenna and a beacon on top.

The regolith would be particularly dark there, but I wonder if it would contain some proportion of the sort of square cornered glass fragments that could act as reflectors, Then torchlight could cast an eery grey light for miles.

Given the risk of solar flares and the problem of heat I wonder why nearside missions weren't timed for the lunar night. Surely the earth would give plenty of light to see by.


I think it's going to be pretty dark. The illiminance of the starry sky as seen from Earth is only 0.00005 lux, compared with 110,000 lux for a sunny sky. That's a factor of 2.2 trillion. Even a quarter moon gives you 0.01 lux, still a factor of 2000 more than starlight. On the Moon, you don't have any atmosphere to scatter the light, but you are not going to get a lot more total illuminance than you get on Earth. At Lunar night, you will be able to see the stars very clearly, but not the regolith you are walking on. Without Earthshine, of course. Check out



This is why some people have proposed we build a space telescope on the far side of the moon. It would be the coldest, darkest and coolest place to have a telescope to get a glimpse of the remains of the Big Bang perhaps.

For almost two weeks each month, that is.
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