Abstractions

摘要

Many stars are surrounded by a swirling mass of interstellar dust, known as a protoplanetary disk. Over millennia, the dust coagulates to form pebbles, then boulders and. eventually, planets. Thousands of such disks exist, but most are too far away for us to study the details and timing of planet formation. On page 194, William Herbst at Wesleyan University in Middletown, Connecticut, and his colleagues use the unique geometry of the system surrounding a star called KH 15D to observe the growth of grain-sized particles from interstellar dust - the first step in the evolution of protoplanetary material. Herbst talks to Nature about the project.