Origin of crystalline silicates from Comet 81P/Wild 2: Combined study on their oxygen isotopes and mineral chemistry.

ABSTRACT: In order to explore the link between comet 81P/Wild 2 and materials in primitive meteorites, seven particles 5 to 15 μm in diameter from comet 81P/Wild 2 have been analyzed for their oxygen isotope ratios using a secondary ion mass spectrometer. Most particles are single minerals consisting of olivine or pyroxene with Mg# higher than 85, which are relatively minor in 81P/Wild 2 particles (~1/3 of the ¹⁶O-poor cluster). Four particles extracted from Track 149 are ¹⁶O-poor and show Δ¹⁷O (= δ¹⁷O - 0.52 × δ¹⁸O) values from -2%₀ to +1%₀, similar to previous studies, while one enstatite (En₉₉) particle shows lower Δ¹⁷O value of -7±4%o (2σ). This compositional range has not been reported among

SUBMITTER: Defouilloy C 

PROVIDER: S-EPMC6350803 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature