Clouds on other planets often interfere with our ability to figure out whether they contain life, The Atlantic reports. The presence of life changes a planet’s chemistry—just like on Earth, where living organisms are the only reason our atmosphere has oxygen gas. Looking for signals of these chemicals in the atmospheres of distant planets is a key part of searching for life outside of Earth. And yet, scientists aiming telescopes at distant planets have discovered over and over again that clouds on those planets get in the way, preventing us from picking up the signals of these distant chemicals. A new orbiting telescope, the James Webb Space Telescope, should be able to see through clouds—but the telescope will be in high demand. So researchers are now working on finding ways around the cloud problem. One way they’re testing is to mimic alien clouds on a small scale in labs on Earth, with the goal of learning about planets’ atmospheres by studying the clouds themselves.