A planetary environment and analysis chamber (PEACh) for coordinated Raman-LIBS-IR measurements under planetary surface environmental conditions

摘要

A planetary environment and analysis chamber (PEACh) has been developed at Washington University in St. Louis, in order to perform in situ multiple spectroscopic measurements on geological samples under relevant planetary environmental conditions and to support future planetary missions, with particular interest on Mars. The pressure in the chamber can range from ambient to 3 × 10 ~(-2) mbar. The simulated atmospheric composition and pressure are regulated via a combination of needle and ball valves connecting the chamber with containers filled with premixed gas. The temperature of the samples can be controlled in a range from ambient to - 100°C. The in situ analytical techniques implemented (and to be implemented) are laser Raman spectroscopy, laser-induced breakdown spectroscopy (LIBS), near-IR reflectance spectroscopy, mid-IR attenuated total reflectance spectroscopy, and microscopic imaging. The coordinated spectroscopic sensing on the same geological sample under well-controlled atmospheric conditions in the PEACh establishes a way to link the results from the laboratory experiments to the spectral data obtained by landed and orbital planetary exploration missions, which will facilitate understanding the surface processes by which mineral phases occur and their association with atmospheric changes.