Journal Highlights

Next Steps Forward in Understanding Martian Surface and Subsurface Chemistry

Commentary in Journal of Geophysical Research-Planets

The presence of oxidants such as hydrogen peroxide (H2O2) and perchlorate (ClO4−), which have been detected on Mars, has significant implications for chemistry and astrobiology. These oxidants can increase the reactivity of the Martian soil, accelerate the decomposition of organic molecules, and depress the freezing point of water. The study by Crandall et al. “Can Perchlorates be Transformed to Hydrogen Peroxide Products by Cosmic Rays on the Martian Surface” reveals a new formation mechanism by which hydrogen peroxide and other potential oxidants can be generated via irradiation of perchlorate by cosmic rays. More

By Brandi L. Carrier, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA

Editor’s Highlight—An explanation for the formation of hydrogen peroxide on the surface of Mars

Understanding the fate of organics on Mars is critical to the search for biosignatures in the near-surface materials. This manuscript illustrates how cosmic radiation acting on perchlorates may produce additional oxidants in the form of hydrogen peroxide (H2O2) that may transform organics. While H2O2 has been detected on the surface of Mars, there have been few explanations of its formation. This paper presents a plausible formation mechanism, based on the presence of the commonly occurring perchlorate salts.