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Immersing the Ryugu grains in solvents and analysing the dissolved compounds has revealed over 20,000 organic species. When liquid water existed on Ryugu shortly after formation, molecules were being built that could become the building blocks for life. Around twenty types of amino acid have been found in the Ryugu grains, which are essential to life on Earth. Many molecules can exist as two mirrored forms, referred to as the “chirality” or “left and right handedness”. But while Earth life uses only left-handed molecules, the chirality of the Ryugu amino acids have been found in roughly equal abundance, suggesting production via non-biological mechanisms. The composition of Ryugu resembles that of the Sun and CI chondrite meteorites. Less than 10 CI chondrites have ever been found on Earth. This can be explained by the fragility of the Ryugu grains, which would disintegrate upon entering the Earth’s atmosphere, never reaching the ground. The CI chondrites that have been discovered are weathered and changed by the Earth’s water. The Ryugu grains are therefore one of the best representations of the chemical composition of our Solar System out of all extraterrestrial samples. Our Astromaterials Science Research Group (ASRG) has therefore started the “Ryugu Reference Project” to determine the chemical composition in detail. (For the full article and references, please refer to ISAS News.)