Martian Clouds Require Higher Humidity than Earth for Cloud Formation, StudyBy Staff Reporter, UniversityHerald Reporter
In an attempt to determine the conditions that give rise to clouds in Mar's atmosphere, researchers at the Massachusetts Institute of Technology (MIT) created Mars-like atmospheric conditions within a three-story-tall cloud chamber in Germany.
The images of Martian sky, taken by NASA's Opportunity rover, depicted gauzy, high-altitude wisps, similar to cirrus clouds found on Earth. Scientists claim that these clouds likely consist of either carbon dioxide or water-based ice crystals. However, it is difficult to conclude without studying a direct sample from Mars. And this is what exactly the MIT researchers are attempting to find out.
After creating conditions similar to the Red planet in the chamber, MIT researchers adjusted the temperature and relative humidity to create Martian clouds. Cloud formation occurred when the researchers adjusted the relative humidity to 190 percent, which is higher than what is required on Earth.
The finding can help create better models of the Martian atmosphere and climatic conditions, as previously it was believed that clouds in Mars require humidity levels similar to those found on Earth. It will also help scientists understand how the planet transports water through the atmosphere.
"A lot of atmospheric models for Mars are very simple," Dan Cziczo, the Victor P. Starr Associate Professor of Atmospheric Chemistry at MIT, said in an official statement. "They have to make gross assumptions about how clouds form: As soon as it hits 100 percent humidity, boom, you get a cloud to form. But we found you need more to kick-start the process."
The MIT team conducted most of the study's experiments during the summer of 2012 in Karlsruhe, Germany, at the Aerosol Interaction and Dynamics in the Atmosphere (AIDA) facility. The facility was once a former nuclear reactor that has been converted into the world's largest cloud chamber.
The facility was originally transformed to examine atmospheric conditions on Earth. But Cziczo realized that with little modifications, the chamber could replicate conditions on Mars. In order to create a successful Martian atmosphere, the researchers first drained out all the oxygen from the chamber, and then filled it with inert nitrogen or carbon dioxide - the most common components found in the Red Planet's atmosphere.
The finding has been published in Journal of Geophysical Research: Planets.