Sulfur as a liquid on Venus

Technical data for the element Sulfur in the Periodic Table.

According to this source the boiling-point of sulfur at 1 atm is 717.87 K (444.72 C) and its critical point is at 1314 K at 204.3 atm. Past that it’s a super-critical fluid – neither liquid nor gas, but a bit of both. We can use those two data points to estimate that at Venus’s surface pressure of 735 K the vapour pressure of sulfur is just 1.3 atm or 1.4% of the atmosphere at 100% humidity. That doesn’t seem too unreasonable and it indicates that large pools of sulfur would be quite stable after erupting from within. A hydrosphere of the stuff could form – if there was enough of it. Magellan’s SAR scanning of the planet didn’t show any dark patches that indicated RADAR absorbing masses of the stuff, but localised deposits might’ve been below Magellan’s resolution limits.

It might seem like an odd thing to focus on as a liquid, but it has been suggested both as a medium of life and as a molecular structural material akin to carbon. Certainly terrestrial life has uses for it and there’s no reason why a different kind of life might not find it as useful as we find carbon to be.