Just for fun.

[Longhorn]

Yes, when necessary.  I have no reason to believe or disbelieve the Titanic sunk, so I accept that it did.  

If a theist used that argument with the god/bible thing, you would call it circular.  What is the difference?

You say the moon exists because we have rocks from the moon.  For sake of argument, I will accept the rocks are extraterrestrial, but that does not prove that they are from the moon.

umm, the difference being the bible is the claim so it can't support itself

you say 'prove god exists', theists says 'Here's the claim that god exists'
you say 'prove the moon exists', I say 'Here's a bit of the moon'

its all in context, there's no reason at all to disbelieve the moon landing and the same people who we have no reason to disbelieve were on the moon give us definitely extraterrestrial rocks and say 'here are bits of the moon'

As I stated above, there is nothing wrong with accepting some that is reasonable, but that is not proof.

what would constitute proof?

I never said we could not see the moon.  Maybe it is a 'Death Star' or a 'Borg Ship'.

Pictures and videos are not proof.  They can be evidence, but I saw a video on YouTube of a bird swooping down into a park and grabbing a kid and flying off with him.

sure, but that video was a different source-someone obviously trying to get views, right?
In the case of pictures of the moon, the source doesn't have any personal interest in convincing you, so it's more reliable

IOW, UR ARGUMENTS SUCK M8