The good debates are the ones where evidence is presented. You might remember a PM fight I had with another poster over the VVAW?<br /><br />The same guy said he believed in the "Nemesis" hypothesis. When that first came out years ago, I said, "nah...those patterns don't work. Could be random, not worth looking into." But when simulation work on Xena showed me that it had to have been perturbed by something to get into it's inclined orbit, I began to suspect there may be such an object. The other poster provided the crucial piece of evidence; lunar soil analysis indicating a renewal of bombardments about 600 million years ago, possibly meaning "Nemesis" was perturbed into it's present orbit at that time. I had rejected the idea because such an orbit could not possibly have lasted the age of the solar system in the face of perturbations by passing stars. The geological evidence cannot stand alone, but there is a growing mass of other evidence.<br /><br />(Closer to this topic) -The same poster, over in M & L, wanted to use psychlopropane (<img src="/images/icons/crazy.gif" />) as a jet fuel. I'm afraid he might get some amateur rocketeer blown up. I searched other similar fuels and discovered that acetylene is a hazardous explosive in solid form. The stuff freezes at -84 degrees C.<br /><br />Some posters would like to find green plants. But as best we can tell right now, the ones on Enceladus are blue. But some of the best enchiladas I have ever had were made out of blue corn tortillas by Sandia Indians in Ysletta, New Mexico.<br /><br />I wonder - ... did chlorophyll take over as the chief biochemical by sheer luck? Could there have been competitors in the early Earth environment which lost out because of simple misfortune? Could it be that there are purple aliens?<br /><br />What life chiefly needs is energy. Since it appears there is a hole in the ice at Enceladus that might let energy through, I would say it would make better sense to check there first,