Kavli Affiliate: Sara Seager
| First 5 Authors: Jane S. Greaves, Paul B. Rimmer, Anita M. S. Richards, Janusz J. Petkowski, William Bains
| Summary:
New analysis is presented of the 1.1 mm wavelength absorption lines in Venus’
atmosphere that suggested the presence of phosphine. We retrieve a sulphur
dioxide observation from the JCMT archive that was simultaneous within a few
days of the PH3 1-0 spectrum obtained in June 2017, and demonstrate via a
radiative transfer calculation that contamination of PH3 by SO2 was ~10 per
cent. We also present ALMA 2019 spectra of PH3 1-0 and an SO2 transition
acquired simultaneously, and infer that SO2 line-contamination was ~2.5 per
cent (for the least-noisy half of the planetary disc). The
contamination-subtracted ALMA and JCMT spectra (of 6-8 sigma confidence) are
now consistent with similar absorption-depths at the two epochs. The two values
span -1.7(+/-0.5) 10-4 of the continuum signal (which was re-estimated for
ALMA), albeit for differing planetary areas. This suggests that the abundance
attributed to phosphine in Venus’ atmosphere was broadly similar in 2017 and
2019.
| Search Query: ArXiv Query: search_query=au:”Sara Seager”&id_list=&start=0&max_results=10