Verification and Validation of DORN Engineering model : Joint Master Program in Space Science and Technology Spacemasters

Abstract: This report presents the various test procedures carried out to verify and validate the engineering model of the DORN instrument. DORN is an instrument designed to perform alpha spectroscopy on the lunar surface, this instrument will be onboard Chang’e 6 lunar mission which is a lunar sample return mission conducted by China. DORN is a French payload developed by CNES (Centre national d’études spatiales) and CNRS (Centre national de la recherche scientifque) for the in situ measurement of Radon on the Moon. The scientifc objective of DORN is to have a better understanding of the lunar surface by studying the transport of gases in the lunar regolith and exosphere and to improve the mapping of Uranium. The radionuclides of interest for DORN are the chains of Rn-222 and Rn-220 which emit alpha particle in an energy range of 5.3 to 8.8 MeV.Due to a sudden change in the location of the landing site of the Chang’e 6 lander, DORN’s range of operating temperature has increased, and the temperature will be much higher than expected. In this report, we will discuss about the testing of the Engineering model of DORN in these new thermal enviornment.This will enable us to determine whether the instrument can survive the mission. Tests are done for verifying the engineering model of DORN. Since these conditions were unexpected, DORN also needs some design modifcations in order to pass all of these tests to get validated. The report discusses the test setup proposed for various testing, analysis of test results, and improvement in design to validate the instrument. The validation of the engineering model will play an important role in fnalizing the design of the fight model and in the calibration of the instrument for the analysis of the data that will acquired during the mission.