WOW.
But honestly, the tradeoffs I would have to make to move somewhere with even blue sky or green sky at this particular point in my life are large enough that they might as well be in Siberia. And I expect it to get worse as I age and entrench. Hence, a bit of jealousy.
The 1950 ones would have been a lot harder to spot, of course, but might at times have reflected the light of the below-the-horizon sun.
And done with Bootstrap ;)
Though, my own recently re-ignited interest in astronomy has taught me that you can actually see quite a bit, including satellites in even thoroughly light polluted areas as my back yard rates red on these charts [1].
What I'm surprised about is that they came up with the theory of "man-made fires" all by themselves.
Yes, you can see a number of satellites from even the densest urban areas. I could usually see three planets from Manhattan. But I never once had the desire to go lie in Central Park after dark and stare at the sky. Compared to that, even yellow sky is amazing. I frequently find myself stopping on the way from the car to the house at night to stare at the sky, and I think to myself: "And this sky isn't even that good."
So I hear about this family, isolated, zero light pollution, probably far enough north for good Northern lights, and it's no wonder to me that they would have noticed satellites. How could they not be staring at the night sky constantly? It must be heart-achingly beautiful there.
And he might very well have at least passing knowledge of the ideas from contemporary descriptions inspired by the writings of Tsiolkovsky on exploration of space starting from 1903 or so onwards, or any number of other sources.