Readily available phosphate from minerals in early aqueous environments on Mars.

If the chemistry essential to life was present in water-containing environments on Mars, the processes that led to life on Earth may have also occurred on the red planet. Phosphate is one of the chemical nutrients thought to be essential for life and is also considered critical to reactions that may have led to life on Earth. However, low prebiotic availability of phosphate may have been a complicating factor in terrestrial abiogenesis, suggesting that a similar hurdle may have confronted the development of life on Mars. Phosphate available for biological reactions can be introduced into aqueous environments through dissolution of primary phosphate minerals during water-rock interactions, but little is known about the dissolution of the dominant phosphate minerals found in martian meteorites and presumably on Mars. Here we present dissolution rates, phosphate release rates and solubilities of phosphate minerals found in martian rocks as determined from laboratory measurements. Our experimental findings predict phosphate release rates during water-rock interactions on Mars that are as much as 45 times higher than on Earth and phosphate concentrations of early wet martian environments more than twice those of Earth. We suggest that available phosphate may have mitigated one of the hurdles to abiogenesis on Mars. [ABSTRACT FROM AUTHOR]