Venus clouds may be 60% water by mass, challenging the sulfuric-acid image

A peer‑reviewed reanalysis of NASA’s 1978 Pioneer Venus data suggests that material trapped in Venus’s middle-to-lower cloud aerosols is about 60% water by mass, with ferric sulphate and sulphuric acid each contributing ~20%. The water is likely bound in hydrated minerals rather than free liquid water, and the finding is provisional, based on an unplanned aerosol collection during descent. While it does not imply life in the clouds, it reopens questions about cloud chemistry and underscores the need for a dedicated aerosol instrument on a future mission (e.g., NASA’s DAVINCI) to test these compositions directly.