In the wake of DORN: a comprehensive lunar sample analysis for radon outgassing

The successful return of samples by the Chang’E 5 and Chang’E 6 missions of the China National Space Administration (CNSA) marks an important milestone for lunar science, offering unprecedented access to a new set of samples from young mare basalts and far-side regolith. This study builds upon the scientific legacy of the DORN (Detection of Outgassing RadoN) instrument onboard Chang’E 6, which performed the first in-situ radon measurements on the Moon. It aims to connect orbital and in-situ measurements with laboratory analysis of lunar regolith.

We present a study investigating the mechanisms governing radon dynamics in the regolith and at the regolith-exosphere interface, including production (emanation) and transport (adsorption). Conducted at the Laboratoire National Henri Becquerel (LNE-LNHB), our approach uses a custom-developed suite of high-sensitivity techniques, including low-level gamma-ray spectrometry, liquid scintillation counting, and a purpose-built gas bench. This methodology is designed to characterise quantities of extraterrestrial material on the order of 1 gram.

Having validated our protocols using lunar analogues, we are currently applying this framework to a returned Chang’E 5 sample. We will present our methodology and discuss preliminary findings on the radioactive content and radon emanation fraction of this sample.