Separation of planetary noble gas carrier from bulk carbon in enstatite chondrites during stepped combustion

The exact location of planetary noble gases in meteorites remains unknown but it is inferred to be closely associated with, if not precisely some portion of, the macromolecular organic material in carbonaceous chondrites [1] . Herein we show that for enstatite chondrites the major carbonaceous component is not the carrier of the gases. This may also be true for other chondritic groups. Rather, these gases are all contained in a minor combustible constituent. This situation has all the hallmarks of a Russian matryoshka doll problem, as was witnessed previously in the study of meteorites prior to the understanding of the presence of presolar grains. A possible conclusion, which is in line with previous suggestions [2] , [3] , is that planetary noble gases are also presolar and located in a new, and as yet unidentified, form of presolar material.