Astrobiology: Life in the Universe

Exobiology and Evolutionary Biology


  1. Laboratory Investigation of the Workman-Reynolds Effect as Applied to Icy Worlds and Snowball Earth

    PI: Kevin Hand

    We will conduct laboratory experiments to investigate the Workman-Reynolds effect (Workman and Reynolds, 1948; 1950) as applied to icy worlds and the Snowball Earth. The Workman-Reynolds effect (hereafter WRE) describes the potential difference that arises across the freezing front of an aqueous solution. During freezing the advancing ice matrix selectively includes some ions while rejecting others, thereby creating potential differences of a few to ~230 volts (Cobb and Gross, 1969; Workman and Reynolds, 1950). The magnitude and sign of the potential depends primarily on freezing rate, the ions in solution, and the concentration of ions.

    As a consequence of the potential arising at the ice-water interface it has been proposed that electrolysis of water could lead to significant O2 production (Workman and Reynolds, 1950). Several workers have measured a reduction in pH of the resulting ice relative to the water (Gross, 1965; Robinson et al., 2006), indicating the incorporation of dissociated hydrogen. Additional chemical processes may also occur at the interface as a result of the WRE. Many aspects of this effect remain unexplored and are not well understood.

    Though considerable good work on the WRE was performed in the 1950’s-1970’s, much of that work focused on the application to electricity in thunderstorms and little to no consideration – even on up through the present-day publications – has been given to the conditions of a Snowball Earth or ice shells on worlds beyond Earth.