Year: 2024
Type: article
Abstract: Aims. Following several reports announcing the detection or non-detection of minor species above the clouds of Venus, we have searched for other possible signatures of PH 3 , HCN, and NH 3 in the infrared range. Methods. Since 2012, we have performed ground-based observations of Venus in the thermal infrared at various wavelengths to monitor the behavior of SO 2 and H 2 O at the cloud top. We have identified spectral intervals where transitions of PH 3 (around 955 cm −1 ), HCN (around 747 cm −1 ), and NH 3 (around 951cm −1 ) are present. Results. From the absence of any feature at these frequencies, we derive, on the disk-integrated spectrum, a 3- σ upper limit of 3 ppbv for the PH 3 mixing ratio, 0.5 ppbv for HCN, and 0.3 ppbv for NH 3 , assuming that these species have a constant mixing ratio throughout the atmosphere. Maps of the Venus disk recorded at the center position of the lines show that there is no evidence for local detection anywhere over the Venus disk. Conclusions. Our results bring new constraints on the maximum abundance of these species at the cloud top and in the lower mesosphere of Venus.
Source: Astronomy and Astrophysics
Institutions: Centre National de la Recherche Scientifique, Université Paris Sciences et Lettres, Observatoire de Paris, Sorbonne Université, Laboratoire d’études spatiales et d’instrumentation en astrophysique, Southwest Research Institute, Université de Versailles Saint-Quentin-en-Yvelines, Université Paris-Saclay, Institut Pierre-Simon Laplace, Laboratoire atmosphères, milieux, observations spatiales, Technical University of Denmark, Kyoto Sangyo University
Language: English
Topic: Astro and Planetary Science
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,732
Funders: National Aeronautics and Space Administration, European Commission, Centre National d’Etudes Spatiales, Centre National de la Recherche Scientifique, Université de Versailles Saint-Quentin-en-Yvelines, Science Mission Directorate, HORIZON EUROPE Framework Programme, Japan Society for the Promotion of Science
Awards: LEARN ABOUT THE TRANSFER OF MOMENTUM VIA WAVES FROM THE TROPOSPHERE INTO THE UPPER ATMOSPHERE. OUR RESULTS WILL PROVIDE NEW AND UNIQUE INFORMATION AB, European Unified Research on Observations of Venus using co-ordinated Space- and Earth-based facilities, ALAN TOKUNAGA/UNIVERSITY OF HAWAIITHE NASA INFRARED TELESCOPE FACILITY: MISSION SUPPORT AND SOLAR S, G547523797
OpenAlex ID: W4402741404