| Autor: |
M. A. Cordiner, K. Darnell, D. Bockelée-Morvan, N. X. Roth, N. Biver, S. N. Milam, S. B. Charnley, J. Boissier, B. P. Bonev, C. Qi, J. Crovisier, A. J. Remijan |
| Jazyk: |
angličtina |
| Rok vydání: |
2024 |
| Předmět: |
|
| Zdroj: |
The Planetary Science Journal, Vol 5, Iss 10, p 221 (2024) |
| Druh dokumentu: |
article |
| ISSN: |
2632-3338 |
| DOI: |
10.3847/PSJ/ad7829 |
| Popis: |
46P/Wirtanen is a Jupiter-family comet, probably originating from the solar system’s Kuiper Belt, that now resides on a 5.4 yr elliptical orbit. During its 2018 apparition, comet 46P passed unusually close to the Earth (within 0.08 au), presenting an outstanding opportunity for close-up observations of its inner coma. Here we present observations of HCN, H ^13 CN, and HC ^15 N emission from 46P using the Atacama Compact Array. The data were analyzed using the SUBLIME non-LTE radiative transfer code to derive ^12 C/ ^13 C and ^14 N/ ^15 N ratios. The HCN/H ^13 CN ratio is found to be consistent with a lack of significant ^13 C fractionation, whereas the HCN/HC ^15 N ratio of 68 ± 27 (using our most conservative 1 σ uncertainties), indicates a strong enhancement in ^15 N compared with the solar and terrestrial values. The observed ^14 N/ ^15 N ratio is also significantly lower than the values of ∼140 found in previous comets, implying a strong ^15 N enrichment in 46P’s HCN. This indicates that the nitrogen in Jupiter-family comets could reach larger isotopic enrichments than previously thought, with implications for the diversity of ^14 N/ ^15 N ratios imprinted into icy bodies at the birth of the solar system. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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