Yun Liu

An ordinary transistor in a phone is made in a vacuum chamber, where atoms are deposited layer by layer. Expensive and slow. But indium oxide can be printed like ink — from a drop of liquid metal that, in air, coats itself with a thin oxide film. The authors took indium, melted it, and rolled it over a substrate at 250 degrees.

The birth of a moon is a cosmic car crash. Two young planets collide, and a cloud of scorching debris swirls around the surviving world. From this disk, like clay on a potter's wheel, a satellite gradually takes shape. That's probably how our Moon came to be.