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NASA NTRS · 20260003981

Evidence of an Extended Period of Aqueous Alteration on the Bennu Parent Body Revealed By I-Xe Analyses

S A Crowther·J D Gilmour·J S Cowpe·L Fawcett·J J Barnes·A N Nguyen·H C Connolly, Jr·D S Lauretta
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Abstract

NASA’s OSIRIS-REx mission delivered to Earth 121.6 g of regolith material from asteroid Bennu on 24th September 2023. We report multi-step laser pyrolysis xenon isotopic analysis to investigate the I-Xe system in individual particles separated from aggregate material (a mixture of small particles of undefined lithology). The high sensitivity of the RELAX mass spectrometer allows us to observe small excesses of individual isotopes and separate out different components, which may not be possible using a conventional noble gas mass spectrometer. The temperature resolution of RELAX is sufficient to seek an I-Xe isochron from step heating analysis of a sample mass <100 μg, which can contribute to our understanding of the nature and timing of aqueous alteration on Bennu’s parent body. We also aim to better estimate and understand the iodine concentration of CI chondrite-like material.

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BibTeXRIS

S A Crowther, J D Gilmour, J S Cowpe, L Fawcett, J J Barnes, A N Nguyen, H C Connolly, Jr, D S Lauretta. 2026-08-09. Evidence of an Extended Period of Aqueous Alteration on the Bennu Parent Body Revealed By I-Xe Analyses. https://ntrs.nasa.gov/citations/20260003981

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