A hypothesis of perchlorate-enabled photosynthesis on MarsAuthor(s): J.E.Brandenburg
It is hypothesized that photosynthetic bacteria on Mars protect themselves from direct contact with the atmosphere by binding oxygen to chloride ions to oxidize them to perchlorate and then excrete the bound oxygen as sodium perchlorate, which binds water so tightly it prevents loss of cell water to the Mars atmosphere even at the low pressures experienced there. Other bacteria then digest the perchlorate and release oxygen to the atmosphere. This photosynthetic pathway is similar to the arsenate based photosynthesis seen in red bacteria found Mono Lake on Earth and is hypothesized to use an organic dye of similar color to preferentially utilize high energy green and blue photons for this photosynthetic process. This hypothesis is proposed to explain the ubiquitous nature of sodium perchlorate on Mars surface, a rare chemical in nature on Earth.