Dear setiamon, I will leave your major question to those of us here who have far more experience than myself, but I have something to note regarding your example question: There is absolutely no problem in travelling in the astral body to the moon, the planets of our physical solar system, or even other galaxies for that matter. I think it is reasonable to assume that Bardon was very much aware that not only astral travel to the moon is possible, but physical travel too ;) As for what is indeed impossible, that is astral travel beyond the zone girdling the earth - which you reffered to as the "earthgrid". This is ~not~ a reference to a physical location, and you should be careful and differentiate the physical planets of our solar system from the metaphysical spheres of the Hierarchy. The spheres are named the same way as the planets by analogy, but it does not make them the same place in any way.