Please Register or Log in to view the hidden image! looking at that image with its empty interior "cavity" it occurred to me that the Sequoia analogy is a vivid one. gravity herding mass from the outside in* corralling it into two rotating fields, one with dust, planets, the other stars. Bit unlike a tree trunk, leaving no substance in the center not even gravity, having drawn all into the ring and star masses. * love to mix metaphors.