Vegetative life on Venus? or investigations with algae which grow under pure CO₂in hot acid media and at elevated pressures

Abstract

Experiments are described with algae grown in a new environment of pure C0 2 under pressure and in an acidic nutrient medium at elevated temperatures. One species found in hotsprings was observed to grow. If the planet Venus has acidic polar seas as we suggest, they may harbor photosynthetic life.

Extremophiles and chemotrophs as contributors to astrobiological signatures on Europa: a review of biomarkers of sulfate-reducers and other microorganisms

“…Life represented by terrestrial extremophiles may have existed in the past elsewhere in the Solar System. A discussion on the possibility of ancient life elsewhere in the Solar System includes Venus in its early cytherean oceans (Seckbach and Libby, 1970). Terrestrial microorganisms can live in similar conditions as presumably primordial biota autochthonous to ancient Venus under high CO 2 , elevated temperature, and even tolerate sulfuric acid.…”

“…Some microorganisms combine diverse adaptations to extreme environments, for example the red unicellular thermoacidophilic Cyanidium caldarium is an enigmatic alga (Seckbach, 1992, 1994a, Pinto, 2007. This rhodophytan grows in very low pH areas (cf., 'halophiles below), at temperatures up to 56-57 0 C. It thrives in media very well bubbled with pure CO 2 (Seckbach et al, 1970). Its cohorts in the family Cyanidiaceae cohabit the same elevated temperature and low pH environments (Seckbach, 1992).…”