Searching for Metallic Frost on Venus

Planetary Sciences doctoral student Sara Port is using computer modeling at Japan’s Okayama University this summer to further her research into “metallic frost” on Venus. Here is her dispatch from the field:

Data collected on Venus from NASA and the USSR orbiters back in the 1970s-1990s detected unusual radar reflecting surfaces on the tops of its mountains. There are several theories on what could cause such a signal, but there is a consensus among the community that it is due to some metallic material, though we have yet to determine the composition. Due to its appearance in high altitude locations it has since been dubbed “metallic frost.”

There are two parts to my research project. The first is to observe how the temperature in the atmosphere of Venus would change if we altered the concentration of the atmospheric components. This will inform us on the stability of Venus’ atmosphere and if it has varied in the past in both temperature and composition. The second part is to model the interaction between the atmosphere and the surface minerals, while taking into consideration the temperature changes modeled in part one.

A strong background in modeling is essential for planetary scientists, since direct access to these planets is beyond our reach and because missions are so rare. These models will help us better understand Venus, as well as the formation of metal frost.

To conduct this research, I have a Venus simulation chamber here at the Arkansas Center for Space and Planetary Sciences that replicates the temperatures, pressures, and atmospheric composition on Venus. I study the interaction between possible metal frost candidates, such as pyrite, pyrrhotite, and bismuth/tellurium/sulfur mixtures, as well as gases found on Venus, such as CO2 (carbon dioxide), SO2 (sulphur dioxide), and COS (carbonyl sulfide) at Venusian temperatures and pressures. My goal is produce a mineral in my chamber that is stable in the cooler, highland conditions and not stable in the hotter, lowland conditions, just like metal frost.