Dear Regner. I am looking forward to your answers in this debate. We will I am sure increase our learning. However, it is my opinion, that there will be no resolution. You asked for 5 challenges for the case supporting geocentrism. Not many were forthcoming. You had to practically drag them out of us. Naturally, because our case on the visible evidence is practically non-existent. Despite what I call the unscientific and unsupported propositions of the cultists, none can deny that the appearances of all the evidence as based on the consensus of practical physics, and I do not include theoretical physics or relativity here, supports a conclusion that heliocentrism is a fact. Almost universal acceptance for centuries would not be possible were it otherwise. Therefore, it has to be obvious, that the real challenge before geocentrism can even be considered, is the existence of the aether. The nature of gravity and almost everything else cannot be turned upside down 'till the aether is a proven reality. (I cannot use the word 'ether' because that is an anesthetic.) It seems to me that you will take the order of answering the simplest and obvious propositions presented first, which are easily dispensed with.. But you will still be left with (a) Failure of the Michelson-Morley experiment - No motion of Earth detected. The aether, which is the essence of Robert Sungenis' detailed analysis. Not what the aether is, but the need for it to be. We know by any search of the internet, that this argument has raged and is still raging, almost forever, in almost every direction. Time may show that you just might have gotten hold of the kangaroo by the tail... Good luck! Philip.