I assume the Sun shining on the flag has faded it some, but is there any other deterioration?
I’d assume not - no atmosphere, right?
Joe
We’ll just have to go there and find out, won’t we? 
True, but because of that lack of atmosphere, the surface is more or less constantly bombarded with micrometeorites. I’d imagine after ~40 years there’d have to be some level of wear from this.
Why should the lack of an atmosphere prevent fading caused by the light of the Sun?
You asked for deterioration other than from the Sun’s light.
Because I believe that sunlight AND exposure to oxygen/nitrogen over a prolonged period is what causes the decomposition of materials such as fabric.
Here is what I wrote:
Then a response came:
That reads as a contradiction of the first part on my statement.
Is this correct?
No, this is what you wrote:
Regardless of what you intended to ask, it’s clear your post as written is asking about deterioration besides that due to sunlight, and that the subsequent reply is addressing that.
I know what I wrote and the response was clearly contradicting the first part.
If you say so. But, just for shits, what say we ask the respondent?
Atmosphere helps, but no it is not generally correct. The very nature of dyes invariably means that they are susceptible to absorbing photons resulting in various radical electronic states that will easily cleave. The Norrish type cleavages are good examples of this. Atmosphere helps, especially oxygen, in that it gives a place for the resulting fragments to go, but eventually a radical will find something else to react with. The end result is that color is gone and the material is deteriorated. No atmosphere is required.
From this ancient thread: The American flag on the moon:
Is there wind on the moon? Strong winds deteriorate flags on Earth faster than anything else.
As you said, the intent of the writer is irrelevant to what was actually written.
Normally I wouldn’t participate in a GQ hijack, but since you’re going along with it, what the hell. Take the following hypothetical:
Poster 1: “I assume A is true, but is B true?”
Poster 2: “I’d assume not.”
You’d interpret Poster 2’s response as saying that A is untrue? Either you parse questions very strangely, or you think that everyone else does.
Is it the parallel structure (“I assume”) that’s throwing you? Even with that, the most obvious interpretation is that it’s a direct response to the question asked (namely, whether or not B is true; Poster 2 is assumes that it is not).
There’s no atmosphere.
How much does a mermaid on Neptune deteriorate over time? The only way to find out is to build rockets that leave earth orbit. The leaflets and handwritten literature that people come to my door to discuss suggest that we might know some day if we build a real rocket like a Saturn V with fuel and actual launch facilities. Hollywood with primitive CGI was good for the time but it is likely we could actually land on the moon if a Chinese fortune cookie said that was the right way to go.
I disagree. If there was a bar with a beautiful view of the earth and 1/6 the gravity, how could you say there is no atmosphere? Travel guide books would be all over that.