Constraints on the flux of meteoritic and cometary water on the Moon from volatile element (N-Ar) analyses of single lunar soil grains, Luna 24 core

► We re-evaluate the origin of N in single lunar soil grains from the Luna 24 core. ► N trapped in lunar regolith is derived from solar wind and a planetary source. ► Non-solar N is supplied by carbonaceous chondrite-like micro-impactors. ► We estimate the recent flux of micro-impactors at the surface of the Moon. ► Water-bearing cosmic dust may represent an important source of water for the Moon.