Researchers at the Massachusetts Institute of Technology were able to recreate Mars-like conditions to form Martian clouds on Earth.
The findings were published in the Journal of Geophysical Research: Planets.
"A lot of atmospheric models for Mars are very simple," said Dan Cziczo, the Victor P. Starr Associate Professor of Atmospheric Chemistry at MIT. "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."
Researchers conducted the study in summer of 2012 in Karlsruhe, Germany, at the Aerosol Interaction and Dynamics in the Atmosphere (AIDA) facility - a former nuclear reactor turned world's largest cloud chamber.
According to MIT's news release, the scientists needed to replicate 190 percent of humidity to form the clouds, along with cold temperatures associated with Mars' atmosphere. In order to recreate the Martian clouds, the AIDA's chamber needed to be tweaked to adapt to the conditions.
"To do this, the team first pumped all the oxygen out of the chamber, and instead filled it with inert nitrogen or carbon dioxide - the most common components of the Martian atmosphere," MIT said. "They then created a dust storm, pumping in fine particles similar in size and composition to the mineral dust found on Mars. Much like on Earth, these particles act as cloud seeds around which water vapor can adhere to form cloud particles."
Once the researchers completed "seeding" the chamber, the temperature needed to be adjusted. The coldest temperature needed to form clouds on Earth is around minus 81 degrees Fahrenheit. In order to create the Martian clouds, researchers dropped the temperatures to minus 120 Fahrenheit. Researchers were able to create 10 clouds in a week, with each clouding taking about 15 minutes to form.
"By adjusting the chamber's relative humidity under each temperature condition, the researchers were able to create clouds under warmer, Earth-like temperatures, at expected relative humidities," MIT said. "These observations gave the researchers confidence in their experimental setup as they attempted to grow clouds at temperatures that approached Mars-like conditions. "
Researchers believe forming clouds is the best way to understand how water is "transported" on Mars.
"If we want to understand where water goes and how it's transported through the atmosphere on Mars, we have to understand cloud formation for that planet," Cziczo said. "Hopefully this will move us toward the right direction."
Learn more about the Martian clouds here.
