Impossiblity - Burden of proof

I agree the burden of proof is on him. He made a claim and you question that claim. You never stated that it could or could not.

I'm not sure if it's relevant that Voyager making these transmissions is commonly accepted as fact, as most who accept it do so without any investigation into the way it is supposed to be achieved. The vast majority of those who believe it to be true would not be aware of the distance involved or the power of the transmitter. It may be that were they aware of these particulars, they would be far less likely to believe in it and it would not be as commonly accepted as true.

Isn’t this partly why an appeal to common knowledge is fallacious – that most people don’t even understand the arguments for and against what it is they believe?

[To Daniel]

I'm not sure if it's relevant that Voyager making these transmissions is commonly accepted as fact, as most who accept it do so without any investigation into the way it is supposed to be achieved.

I accept that cars work yet I can never explain how they do. In reasonable debate, we accept facts; not argue them. Of course, there are ideas that are disputed and wouldn't fall under "fact." I have no idea if this falls under that category.

I don't list "appeal to common knowledge" as a fallacy, not sure many do. I found this to be a "fallacy" pushed by conspiracy theorists who try to cast doubt on facts and reality.

This shouldn't be confused with appeal to common belief (note the last word).

Thank you Bo,

Yes, appeal to common belief is what I meant.

When it comes to cars, we have evidence that they work by using them and even if we don't understand how they work, the fact that they do is a fact of our reality. Voyager is different because none of us have any experience of its operation, or the operation of any deep space probe, we are totally reliant on information from a government institution that Voyager even exists. For this reason, I don't think Voyager falls under the usual definition of fact.

If you built a simple rfc circuit and provided it with power, you might not know that your 10^-8 mw "noise" was more than a line on your neighbor's tv that they might merely be slightly annoyed about, as it "twitched" their picture.  It is unlikely they would contact the FCC.

The data from 10^7 light years away includes resolvable info about the stars' spectrum. 

So, here we are, and I say they can send/receive info at merely <0.1 LY.  One of us is correct, but without your own knowledge of how the electronics works, you can be misled by the conspiracy theories/theorists. There is a danger, of course, that the Michelson-Morley experiment erred.  https://en.wikipedia.org/wiki/Michelson%E2%80%93Morley_experiment. If the data was incorrect outside the measurement limits, there will be many embarrassed physicists.  

Very few have the means to double-check, imo, and it's more likely the doubters are wrong, again imo.

Ultimately, this is an example of demonstrable/falsifiable fact (evidence), not of rhetoric or fallacy.

The claim is also being made that NASA is lying.  Established knowledge is irrelevant, that is the appeal to common sense.  You have to prove claims of deceit, you cannot just assume them to be lying because they disprove your wider theory about the limitations of radio transmissions.  'All evidence against my thesis is fabricated because my thesis is true' is not a valid argument. 

The thing is, the conversation did not start with X making that claim, and X never went on to make that claim.

It started with Y making the claim that the transmissions are impossible, backed up first with sheer incredulity and then, when challenged, following up with false a equivalence between Earth radio and space transmissions.

Y's part in the debate was only to counter the evidence presented by X.

You may be right, but I read it differently. The way I read it is the statement: “Recently I got into a discussion where someone expressed their incredulity” is supposed to be a third party. Then, lower down, we see: “At no point in the discussion did I positively claim that NASA is truly still receiving transmissions from Voyager, or even that voyager really exists,...” Which (to me) says the “someone” in the first part is actually the person making the claim but does not want to make that clear. That is why I restated what I understood was the substance of the problem presented. 

Ok, thanks, I probably didn't explain it clearly enough in the first place.