Dust Composition of Comet 81P/Wild 2 From JWST Spectroscopy Compared to Stardust’s Fine-Grained Materials and Gems-Rich IDPS

D H Wooden; N X Roth; D E Harker; C E Woodward; M S P Kelley; D Bockelee-Morvan; S Milam; J P Bradley; D E Brownlee; H A Ishii

NASA NTRS · 20260000876

Dust Composition of Comet 81P/Wild 2 From JWST Spectroscopy Compared to Stardust’s Fine-Grained Materials and Gems-Rich IDPS

D H Wooden·N X Roth·D E Harker·C E Woodward·M S P Kelley·D Bockelee-Morvan·S Milam·J P Bradley·D E Brownlee·H A Ishii

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Abstract

The Stardust Mission returned samples from the coma of Jupiter Family comet 81P/Wild 2 for detailed laboratory analyses. Here we present and discuss the best-fit thermal dust model for the coma dust of comet 81P/Wild 2 as observed by JWST. Comet 81P was observed through JWST GO 018xx, using NIRSpec (2.9–5.3µm, λ/∆λ≈1000) and MRS IFU (4.9–28.1µm, λ/∆λ≈3000) on 2023-03-20 UT and 2023-03-24 UT, respectively, at a heliocentric distance of 1.85 au and JWST distance of 1.43 au (phase angle of 32 degrees). The dust coma of 81P as revealed by JWST offers a salient compliment to laboratory studies of Stardust samples that typically are bigger than 2 µm and up to 60 µm in size.

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BibTeX RIS

D H Wooden, N X Roth, D E Harker, C E Woodward, M S P Kelley, D Bockelee-Morvan, S Milam, J P Bradley, D E Brownlee, H A Ishii. Dust Composition of Comet 81P/Wild 2 From JWST Spectroscopy Compared to Stardust’s Fine-Grained Materials and Gems-Rich IDPS. https://ntrs.nasa.gov/citations/20260000876

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