NITROGEN COMPONENTS IN LUNAR SOIL-12023 - COMPLEX GRAINS ARE NOT THE CARRIER OF ISOTOPICALLY LIGHT NITROGEN

High-resolution stepped combustion is used to release isotopically dis tinct N components of different thermal stability in lunar soil 12023. The isotopically light gas in this soil appears to be the same as tha t found in the lunar breccia 79035, but the latter material has little of an isotopically heavy component of only slightly lower thermal sta bility. Complex grains in 12023, which probably only release their N o n melting, contain a mixture of the heavy and light N in approximately the same proportions as the unaggregated soil. Ideas that require com plex grains to be enriched in a light-N component, synonymous with the ancient solar wind, therefore, cannot be correct. The implications fo r models invoking solar-wind secular variation are discussed.