Direct Measurement of the Composition of Aqueous Fluids from the Parent Body of Asteroid 162173 Ryugu
Imaging using X-ray absorption contrast by synchrotron nano-computed tomography (47.4 nm/voxel, 7keV) of a Ryugu pyrrhotite crystal (C0002-FC012-from the second touch-down site) revealed probable fluid inclusions (Fig. 1A,B) [1]. The inclusions were completely encapsuled in pyrrhotite, suggesting the fluids were trapped in the early stages of crystal growth, and filled with low-Z material. We performed Time-of Flight-Secondary Ion Mass Spectrometry (TOF-SIMS) depth profiling and high-resolution map-ping at -120°C to exposure and measure the composition of the trapped fluids in a frozen state.