CDR Okay, Houston...let me comment that it certainly is a stark place here at Fra Mauro. I think it's made all the more stark by the fact that the sky is completely black...
CC Okay, Al, beautiful. We can see you coming down the ladder right now. It looks like you're about on the bottom step. On the surface.
CDR Okay, you're right. Al is on the surface. And it's been a long way, but we're here.
Please make a note of what he said about the sky being completely black. But where are the stars?!
On earth we see the stars in the sky because there is little other light. Those who live in mountainous country can go up into the mountains where the air is thin and there are no distracting lights, the stars are quite magnificent. But when you return to the brightly lit city and look at the same night sky, you see only the brightest stars. If you go inside the house and turn on all the lights and look out the window, you can't see any stars.
Why not?
Because the human eye has adjusted to the amount of light, first by adjusting the iris and then by changing the chemical composition of the retina to make it more or less sensitive. In the pitch blackness of the mountains they're open just as wide as they can be, allowing more light to enter. In the night city, they close somewhat to adjust for the street lights. And inside the house, they are as closed as they are during the daytime in sunlight. A camera's aperture works the same way. To set the exposure for bright exposure means that subtle lights like stars simply won't show up.
Because the sky on the moon is black, we tend to believe the viewing conditions are the same as night on earth. Not true. The sun shines just as brightly (slightly brighter, in fact) on the lunar surface, and so the astronauts' eyes (and camera apertures) were set for photographing in daylight conditions. Neil Armstrong reported not seeing any stars from the lunar surface, except through the navigation scopes (where the eyepiece screened out the other lights). Ed Mitchell reported seeing stars only when he specifically shut out extraneous light.
It might be counterintuitive to people stuck on Earth, but once you get to know space, it makes a lot of sense. Contrast to the experience in lunar orbit, as recounted by Apollo 15's CMP, Al Worden:
I curved around the moon to where no sunlight or Earthshine could reach me. The moon was a deep, solid circle of blackness, and I could only tell where it began by where the stars cut off. In the dark and quiet, I felt like a bird of the night, silently gliding and falling around the moon, never touching.
I turned the cabin lights off.
There was no end to the stars. I could see tens, perhaps hundreds of times more stars than the clearest, darkest night on Earth. With no atmosphere to blur their light, I could see them all to the limits of my eyesight. There were so many, I could no longer find constellations. My vision was filled with a blaze of starlight.
I've been seeing moon hoaxers spewing nonsense online recently, so I felt compelled to share that. Anyway, Shepard's waiting a decade pales in comparison to the more than five I've been waiting for us to get back to the moon, but I can be patient for what one hopes is Artemis II's successful flight next month (or even later).
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