Venus: January 2021

Recently published ALMA observations suggest the presence of 20 ppb PH3 in the upper clouds of Venus. This is an unexpected result, as PH3 does not have a readily apparent source and should be rapidly photochemically destroyed according to our current understanding of Venus atmospheric chemistry.

The observation of a 266.94 GHz feature in the Venus spectrum has been attributed to PH3 in the Venus clouds, suggesting unexpected geological, chemical or even biological processes.

The depletion of SO2 and H2O in and above the clouds of Venus (45 -- 65 km) cannot be explained by known gas-phase chemistry and the observed composition of the atmosphere.