[More OT info]Originally posted by Scott Martin:
(Physical Sciences Warning)
Ah the joys of "Magic Number" theory...
An explanation of "Magic Number Theory" for the non-chemist readers:
Some elements are more stable (from a nuclear chemistry point of view) than others, and it appears to be based on the configuration of their nucleus. Lead and Iron are extremely stable, Uranuim and Plutonuim are not (IIRC Plutonuim only exists as a manmade material, generated by neutron bombarding uranium) Extrapolating out from our current understanding of trends in the periodic table, there should be "islands" of stability somewhere in the trans-uranics, way past element 100. (Element 126-128 is the range that I have heard for the beginning of stability my eyes glaze over when people discuss the right "mix" of protons and neutrons) Unfortunately the only way that we have come up with to "create" these elements is to smash nucleii togehter with a particle accellerator, so it's an open question as to the actual stability of elements that are created this way. Do they decompose (fragment) because they are unstable, or because the residual energies of the collision break them up?
Scott (too geeky by half) Martin
The elements at 126-128 are predicted to be stable in the sense that they are radioactive but with half-lives on the order of millions of years. For non-chemist/physicists the half life is where about half of the substance remains, but portions of the substance can remain for many, many half lives. If you start out with enough, you wil still have measurable quantities many half-lives down the road.
edit: they actualy shouldn't break up (if formed) do to the collision energy, the break up of elements formed in particle accelerators is due to their inherent instability (radioactive decay) for some of the more stable elements they actually build up enough matter to do experiments on.
I see what you are talking about though, with molecules (bonds mediated by the interactions of electrons) formation by collision can dump enough energy into molecular bonds so that fragmentation results. With the nucleus, once you get over the repulsive barrier of the electrons, at short ranges the strong nuclear force takes over. Certainly some mesons, etc. might get radiated (that's where extra energy can go) but the formed element will not fragment due to energy from the collision itself. Of course not all collisions will produce the element.
On earth people try to get to this island by smashing transuranics into things at high energy. Even at higher TL how cost effective will it be to samsh enough atoms to get kg quantities or more required for a spacecraft. Space, however, has many ways of smashing things together on a grand scale hard enough to form heavy elements, one of which would be supernovas. This could make for some very interesting "mining" scenarios in dangerous regions and make some unihabitable systems strategically important.