Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Matters Arising
  • Published:

Reply to: No evidence of phosphine in the atmosphere of Venus from independent analyses

Nature Astronomy volume 5, pages 636–639 (2021)Cite this article

Subjects

The Original Article was published on 16 July 2021

replying to G. L. Villanueva et al. Nature Astronomy https://doi.org/10.1038/s41550-021-01422-z (2021)

In their Matters Arising, Villanueva et al.1 state that they are not able to retrieve the signal we presented in our paper2, which we attributed to the presence of phosphine in the atmosphere of Venus. Villanueva et al.1 bring processing, contamination and retrieval arguments in support of their thesis. We address the arguments one by one below, organized into categories of data source, and then signal attribution to phosphine versus sulfur dioxide.

This is a preview of subscription content, access via your institution

Access options

Buy this article

  • Purchase on Springer Link
  • Instant access to full article PDF
Buy now

Prices may be subject to local taxes which are calculated during checkout

Fig. 1: Assessing the origin of the ALMA spectral line.
Fig. 2: Assessing the identification of the JCMT line.

Data availability

Recalibrated ALMA data are also available from the public archive under project id 2019.A.00023.S. The calibrated JCMT data are available from the public archive under project id S16BP007.

Code availability

The scripts we developed to produce the ALMA PH3 spectra following ‘JAO-based’ processing are available in the Supplementary Software. The scripts uid…2020Nov.py apply Callisto bandpass solutions, and imaging options are in scriptForImAllCallinBPTEST202Nov.py.

References

  1. Villanueva, G. et al. No evidence of phosphine in the atmosphere of Venus from independent analyses. Nat. Astron. https://doi.org/10.1038/s41550-021-01422-z (2021).

  2. Greaves, J. S. et al. Phosphine gas in the cloud decks of Venus. Nat. Astron. https://doi.org/10.1038/s41550-020-1174-4 (2020).

  3. Greaves, J. S. et al. Addendum: Phosphine gas in the cloud deck of Venus. Nat. Astron. https://doi.org/10.1038/s41550-021-01423-y (2021).

  4. Thompson, M. A. The statistical reliability of 267-GHz JCMT observations of Venus: no significant evidence for phosphine absorption. Mon. Not. R. Astron. Soc. Lett. 501, L18–L22 (2021).

    Article  ADS  Google Scholar 

  5. Sandor, B. J. & Clancy, R. T. First measurements of ClO in the Venus atmosphere—altitude dependence and temporal variation. Icarus 313, 15–24 (2018).

    Article  ADS  Google Scholar 

  6. Shao, W. D., Zhang, X., Bierson, C. J. & Encrenaz, T. Revisiting the sulfur–water chemical system in the middle atmosphere of Venus. J. Geophys. Res. Planets 125, e2019JE006195 (2020).

    Article  ADS  Google Scholar 

  7. Encrenaz, T., Moreno, R., Moullet, A., Lellouch, E. & Fouchet, T. Submillimeter mapping of mesospheric minor species on Venus with ALMA. Planet. Space Sci. 113, 275–291 (2015).

    Article  ADS  Google Scholar 

  8. Lincowski, A. P. et al. Claimed detection of PH3 in the clouds of Venus is consistent with mesospheric SO2. Astrophys. J. Lett. 908, L44–L52 (2021).

    Article  ADS  Google Scholar 

  9. Mogul, R., Limaye, S. S., Way, M. J. & Cordova, J. A. Venus’ mass spectra show signs of disequilibria in the middle clouds. Geophys. Res. Lett. 48, e2020GL091327 (2021).

    Article  ADS  Google Scholar 

  10. Krasnopolsky, V. A. in Venus (eds Hunten, D. M. et al.) 459 (Univ. Arizona Press, 1983).

  11. Lane, W. A. & Opstbaum, R. High altitude Venus haze from Pioneer Venus limb scans. Icarus 54, 48–58 (1983).

    Article  ADS  Google Scholar 

  12. Luginin, M. et al. Scale heights and detached haze layers in the mesosphere of Venus from SPICAV IR data. Icarus 311, 87–104 (2018).

    Article  ADS  Google Scholar 

  13. Encrenaz, T. et al. A stringent upper limit of the PH3 abundance at the cloud top of Venus. Astron. Astrophys. 643, L5 (2020).

    Article  ADS  Google Scholar 

  14. Hoffman, J. H., Hodges, R. R., Donahue, T. M. & McElroy, M. B. Composition of the Venus lower atmosphere from the Pioneer Venus mass spectrometer. J. Geophys. Res. Space Phys. 85, 7882–7890 (1980).

    Article  ADS  Google Scholar 

Download references

Acknowledgements

The team of ref. 2 thank the many ALMA staff who contributed tirelessly and speedily to this reprocessing project, developing new tests and techniques in a very short time period. The work was led from ESO with input from JAO and NAASC. This paper makes use of the following ALMA data: ADS/JAO.ALMA#2019.A.00023.S. ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada), MOST and ASIAA (Taiwan) and KASI (Republic of Korea), in cooperation with the Republic of Chile. The JAO is operated by ESO, AUI/NRAO and NAOJ.

Author information

Authors and Affiliations

  1. School of Physics & Astronomy, Cardiff University, Cardiff, UK

    Jane S. Greaves

  2. Jodrell Bank Centre for Astrophysics, Department of Physics and Astronomy, The University of Manchester, Manchester, UK

    Anita M. S. Richards

  3. Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA

    William Bains, Sara Seager, Janusz J. Petkowski, Clara Sousa-Silva & Sukrit Ranjan

  4. Department of Earth Sciences, University of Cambridge, Cambridge, UK

    Paul B. Rimmer

  5. Cavendish Astrophysics, University of Cambridge, Cambridge, UK

    Paul B. Rimmer

  6. MRC Laboratory of Molecular Biology, Cambridge, UK

    Paul B. Rimmer

  7. Department of Physics, Imperial College London, London, UK

    David L. Clements

  8. Department of Physics and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA, USA

    Sara Seager

  9. Department of Aeronautics and Astronautics, Massachusetts Institute of Technology, Cambridge, MA, USA

    Sara Seager

  10. School of Physical Sciences, The Open University, Milton Keynes, UK

    Helen J. Fraser

Authors
  1. Jane S. Greaves
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Anita M. S. Richards
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. William Bains
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Paul B. Rimmer
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. David L. Clements
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Sara Seager
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Janusz J. Petkowski
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. Clara Sousa-Silva
    View author publications

    You can also search for this author in PubMed Google Scholar

  9. Sukrit Ranjan
    View author publications

    You can also search for this author in PubMed Google Scholar

  10. Helen J. Fraser
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

J.S.G. and A.M.S.R. contributed conceptualization and investigation; J.S.G., A.M.S.R., S.S. and J.J.P. contributed to the original draft preparation; J.S.G., S.S., J.J.P., C.S.S. and P.B.R. contributed to review and editing; and J.J.P. W.B., S.S., C.S.S., S.R., D.L.C., P.B.R. and H.J.F. contributed expertise to the final draft preparation. All authors have read and agreed to the published version of the manuscript.

Corresponding author

Correspondence to Jane S. Greaves.

Ethics declarations

Competing interests

The authors declare no competing interests.

Additional information

Peer review information Nature Astronomy thanks the anonymous reviewers for their contribution to the peer review of thiswork.

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Extended data

Extended Data Fig. 1 Comparing the limitations found in all-baseline data.

Top: (y-offsets for clarity only) ‘JAO/Berkeley-CASA’ whole planet spectrum, digitised from Villanueva et al.1 and converted to flux-density using the standard Venus model of ref. 2. The overlaid red-dashed curve is our radiative transfer model for PH3, scaled for a fixed 1 ppb abundance, as a guide to detection limits. Bottom: our equivalent whole-planet spectrum following similar processing (Supplementary Information) and subtracting a 2nd-order polynomial as in ref. 1.

Extended Data Fig. 2 Investigating alternative atmospheric models.

Left: ad-hoc altitude-profile with eddy diffusion coefficient Kzz greatly increased in the mesosphere compared to the sparse in situ constraints (Venera 9/1010; Pioneer11; purple shaded region is from Luginin et al.12). Middle: corresponding atmospheric profile of PH3, compared to the ref. 2 profile. The red bar illustrates <5 ppb of PH3 from 10 micron IR-observations13. The fixed 100 ppb of PH3 at lower altitudes illustrates a possible abundance from Pioneer Venus; the instrument-calibration description14 suggests tens to hundreds ppb for the count rate extracted by Mogul et al.9. Right: the PH3 1-0 line that would be observed in this test model, along with the flat profile that the ref. 2 photochemistry would have produced.

Supplementary information

Supplementary Information

Supplementary Figs. 1–3 and Discussion.

Supplementary Software

The data can be re-reduced taking the known issues into account: using a recent version of CASA to improve the primary beam correction, correct use of the model for Callisto as bandpass calibrator, and an option for deriving the bandpass table from Callisto using averaging followed by smoothing. Scripts are uid___A002_Xd90607_X10526.ms.scriptForCalibrationTEST2020Nov.py and uid___A002_Xd90607_X10f75.ms.scriptForCalibrationTEST2020Nov.py. Various imaging options based on this calibration are included in scriptForImAllCallinBPTEST202Nov.py.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Greaves, J.S., Richards, A.M.S., Bains, W. et al. Reply to: No evidence of phosphine in the atmosphere of Venus from independent analyses. Nat Astron 5, 636–639 (2021). https://doi.org/10.1038/s41550-021-01424-x

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/s41550-021-01424-x

This article is cited by

Search

Advanced search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing