When we look at the moon, we always see the same features. It rises and sets, and for millennia people have looked up at the moon in wonder. And many think this to have been an important part of human culture, as it inspired us to reach high and someday visit the moon.
I wonder what the reverse might have been.
An important part of ancient astronomy was the view that all celestial bodies revolve around the earth. That view would NOT have been held by any intelligent life that happened to grow on our moon.
The earth – as viewed from the moon – is always in the exact same portion of the sky. To someone in the center of the part which we can see from earth, earth hangs at the center (top?) of the sky. To someone closer to the periphery of the area which we can see from earth, the earth would be closer to the horizon. But for any one location on the moon, the earth is in one specific part of the sky. It does rotate on its axis, so that you can see Asia, then Europe and Africa, the Americas, and then Asia again. But only in that one spot of the sky.
How odd! (… for us Terrans, anyway …)
So my question is: Suppose that instead of keeping one face to the earth, the moon instead would have been in a geosynchronous orbit, so that it would appear to always be in one part of the sky. (And whether it is physically possible or not, let’s also say that it would be have the same apparent size as it does now.) How do you think human life, science, culture, whatever, might have evolved differently?
I doubt anything noticeable would have changed at all. Your assumption that intelligent moon people would have HAD to have assumed that everything did NOT revolve around them is faulty.
On earth there was good evidence against an earth centric cosmos but it was ignored or squashed. Galileo was threatened with excommunication and placed under house arrest for suggesting the earth wasn’t the center of the universe.
The earth sitting in one place in the sky is no worse than watching Mars apparently backing-up in its orbit (as earth catches up to and passes Mars during its orbit from earth it appears as if Mars stops, moves backwards a bit and then starts forward again). Some really kooky cosmologies were invented to try and explain that away but as Occam’s Razor suggests the simple answer was the right answer…Mars does not orbit the earth.
So, I doubt anything much would have changed. The local Moon-Shaman would have come up with some explanation that the ignorant masses would buy and that’d be that.
I agree with Jeff_42, the human capacity to rationalize ways to maintain the geocentric mindset is stubborn. To this day…all evidence aside, many people still believe that we are at the center of the universe. Most people believe that humanity is the whole purpose of the universe (as part of the glory of God). And without any evidence one way or the other, many people conclude that humans are the only intelligent life in the whole universe. I suspect that a stationary moon would be incorporated into a geocentric belief.
But, as you say, it would be interesting to speculate on how the details of society’s evolution may have differed.
I always seem to be the one doing this, but Robert Heinlien wrote about this! (Or about a similar idea.)
He postulated in one of his short stories that, if the moon did not hang so invitingly in the night sky, man would never have ventured off of the planet. I tend to agree… there is something about the way it hangs up there that just begs you to jump on up and explore. But the rest of the night sky? Not the same thing at all.
As far as Ptolemic cosmology goes, the crystal sphere said to hold the Moon would just be stationary. If anything, I’d think that a geostationary Moon would have added aestetic appeal to the geocentric model. The Earth and the Moon both being stationary makes more sense than the Earth spinning on its axis and the Moon following it around. (Strangely enough, the astronomer’s love of the Copernican principle is at work in my reasoning: I’m rebelling against the contrived situation of the Moon being in geosynchronous orbit by saying that it would be a very strange coincidence, and modern scientists despise coincidences! Maybe this point isn’t valid!)
Now, the Moon not being tidally locked would have much more interesting ramifications. Celestial objects were not observed to be spinning on their axes until Galileo used his telescope and saw things like sunspots. If we could watch the Moon whirling, showing us different features each night, I’d think some bright fellow would wonder if the Earth was spinning on its axis in the same manner! That doesn’t necessarily displace it from the center of the universe, of course, but it does introduce important concepts like motion at great speed that is (practially) undetectable to us.