Most clouds on Earth are made of water, but beyond our planet they come in many chemical varieties. The top of Jupiter’s atmosphere, for example, is blanketed in yellow-hued clouds made of ammonia and ammonium hydrosulfide. And on worlds outside our solar system, there are clouds composed of silicates, the family of rock-forming minerals that make up over 90% of Earth’s crust. But researchers haven’t been able to observe the conditions under which these clouds of small dust grains form.