As others have said, the moon "shines" by reflecting sunlight. It also will reflect "earthlight", more properly sunlight having been reflected by earth. This is often most visible during the crescent moon phases.
I think the guys who went to the moon 40 years ago were fascinated by what they saw, just as you and I are by what we see. The big difference is that they were "up close and personal" with the moon back in 1969 and the early 1970s.
Their view of the earth likely had a similar effect, when they saw the earth from the moon it was about 4 times larger in their field of view than the moon is from earth.
By the way, the moon is quite visible during the daytime on many days, but is just less obvious because the sky is bright. We often used the moon to get a 2-d fix, back in the days of sextant and compass navigation. The sun alone would only give a 1-d fix (or line of position), while a second (1-d fix) line of position from the moon or Venus (yes, Venus can often be seen during the day if you can tell where to look) could cross with the first and give a 2-d fix comparable to the star fixes we'd get at dusk and dawn.
Not too long ago the moon and Venus were near each other in the sky in mid afternoon, and the moon was a good guidepost for finding Venus.
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