Oral Sessions (Day1, Day2, Day3)
Oral Sessions
- Day 2, May 20（Thu.） 11:00-11:20 Room C (Zoom)
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2C-O8-1100 PDF
Multi-isotopic analyses of asteroid samples returned by the Hayabusa2 mission
The sample-return mission Hayabusa2 conducted two sampling sequences that collected ~5 g of the surface and sub-surface materials from a C-type asteroid, Ryugu in 2019. To characterize the collected asteroidal materials, we have developed a technique for a multi-isotopic analysis that uses ~ 30 mg of the Ryugu sample. Two terrestrial basalts and two CM chondrites were chosen as the analog samples to evaluate the performance of the developed technique. The powdered sample was decomposed by a mixture of HF + HNO3 in a Teflon vessel. The sample was conditioned with HBr for the separation of Pb by anion exchange chromatography (AG1-X8), followed by the separation of Ti+Zr+Hf, W, and Mo by AG1-X8, Fe and U by AG1-X8, Sr and Ba by Sr Resin, REEs by RE Resin, Ca by DGA-n Resin, Cr by 1:1 mixture of AG50W-X8 and AG50W-X12, and Mg and Ni by Ni Resin. The recovery yields of individual target elements are generally >90% during each step of the chromatography. The isotopic compositions of the analog samples, especially for Cr and Ti, will be reported in the presentation.