Upper limits of PH3 in the Venus atmosphere from mm spectra observed with the IRAM-30m telescope
- 1CNRS Obs. Paris-Meudon, LESIA, Meudon, France (raphael.moreno@obspm.fr)
- 2IRAM, France
- 3IRAM, Spain
Knowing the controversy about the presence (or not) of phosphine (PH3) on Venus’ atmosphere, we have obtained spectra of Venus in the millimeter domain to constrain PH3 with new measurements.
Our observations -performed on Nov. 09th, 11th and 16th 2020- used the IRAM-30m single dish telescope located in Granada, Spain. to search in Venus’ atmosphere for the PH3(1-0) rotational lines at 266.944 GHz, and the CO(2-1) and 13CO(2-1) lines at 230.538 and 220.398 GHz, respectively. These disk-averaged measurements were obtained with an angular resolution of ~10” (HPBW) while Venus’ angular diameter was ~12.5”.
These measurements have not shown any PH3 spectral signature, while the CO and 13CO lines were detected as expected.
We will present the data analysis of these observations, and use radiative transfer modelling to constrain the abundance upper limits of PH3, and other minor species (HDO, SO and SO2) present in our spectra.
How to cite: Moreno, R., Lellouch, E., Kramer, C., Paubert, G., and Sanchez, M.: Upper limits of PH3 in the Venus atmosphere from mm spectra observed with the IRAM-30m telescope, Europlanet Science Congress 2022, Granada, Spain, 18–23 Sep 2022, EPSC2022-745, https://doi.org/10.5194/epsc2022-745, 2022.
