I guess the only reason that I called it Mars was because that's what I have heard since the game came out but now that I know that Thank You! Because that means that the "Mars" portal is the past and the "Venus" portal is the future or atleast that's what makes since to mean and I heard that the secret lays in between the past and the future but now in the present I cannot remember where I seen that at but I am pretty sure it was in the forums on here so that leads me to believe that the 3rd theory would be my best bet to try because when you have people in all 3 areas the past present and future you can warp time by going back through the main door with either the time piece or the vex because when entering the portals with either of those after atheon you do not get marked so I am lead to believe with a person at each of the main doors in the portals and out it will open.

I love all these ideas and theories people have about the Vault. Really hope one of them turns out to be true.