Have you ever seen a Martian cloud up close? Now you can!
This is Sandra Tsing Loh with the Loh Down on Science.
Clouds over Mars don't look alien. They're wispy and light, like cirrus clouds here at home. Scientists don't know exactly how they form, and they can't just bring one into the lab for analysis. But they wanted to improve their climate models for Mars.
So researchers from MIT recently went to Germany to conduct an experiment we call, "Mars in a Jar." Okay, it's a three-story jar. It was a nuclear reactor. Now it's the world's largest cloud chamber.
To make alien clouds, the scientists replaced the oxygen with nitrogen or carbon dioxide—like on Mars. They added dust, since you need teeny particles for moisture to condense on, a process called nucleation. Then they dropped the temperature to waaaay below frrrrrreezing. Minus 120 fahrenheit—the chamber's lowest temperature, which is like a summer's day on Mars!
Finally, they tweaked the humidity. When the water content was high, higher than needed for cloud formation on Earth, clouds finally formed.
Making little green men—still a stretch. But never say never.
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The Loh Down on Science is produced by LDOS Media Lab, in partnership with the University of California, Irvine, and 89.3 KPCC. And made possible by the generous support of the Gordon and Betty Moore Foundation.