Yichen Zhang

Optical fiber transmits light, but along the way it jitters and dims. To ensure that two parties at opposite ends of the line get the same set of random numbers for encryption, the receiver uses a digital corrector, like noise-canceling headphones that subtract the street hum but sometimes also eat the quiet notes of the music.

In a dense cloud of gas and dust where massive stars are born, two young stars recently passed very close to each other. Their dance has lasted only about sixty years, and astronomers have now seen it in detail for the first time.