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Updated: Aug 2, 2026

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
Measurements of 12C/13C, 14N/15N, and 32S/34S ratios in comet Hale-Bopp (C/1995 O1)
D C Jewitt1, H E Matthews, T Owen
1Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822, USA.
Abstract:
The 12C/13C, 14N/15N, and 32S/34S isotope ratios in comet Hale-Bopp (C/1995 O1) were determined through observations taken with the James Clerk Maxwell Telescope. Measurements of rare isotopes in HCN and CS revealed isotope ratios of H12CN/H13CN = 111 +/- 12, HC14N/HC15N = 323 +/- 46, and C32S/C34S = 27 +/- 3. Within the measurement uncertainties, the isotopic ratios are consistent with solar system values. The cometary volatiles thus have an origin in the solar system and show no evidence for an interstellar component.
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