doi.eso.org

• Andrews, Sean M. [Harvard-Smithsonian Center for Astrophysics, Massachusetts, USA]
• Huang, Jane [Harvard-Smithsonian Center for Astrophysics, Massachusetts, USA]
• Pérez, Laura M. [Universidad de Chile, Santiago, Chile]
• Isella, Andrea [Rice University, Houston, USA]
• Dullemond, Cornelis P. [Universität Heidelberg, Germany]
• Kurtovic, Nicolás T. [Universidad de Chile, Santiago, Chile]
• Guzmán, Viviana V. [Joint ALMA Observatory, Santiago, Chile; Pontificia Universidad Católica de Chile, Santiago, Chile]
• Carpenter, John M. [Joint ALMA Observatory, Santiago, Chile]
• Wilner, David J. [Harvard-Smithsonian Center for Astrophysics, Massachusetts, USA]
• Zhang, Shangjia [University of Nevada, Las Vegas, USA]
• Zhu, Zhaohuan [University of Nevada, Las Vegas, USA]
• Birnstiel, Tilman [Ludwig-Maximilians-Universität, Munich, Germany]
• Bai, Xue-Ning [Institute for Advanced Study and Tsinghua Center for Astrophysics, Beijing, China]
• Benisty, Myriam [Universidad de Chile, Santiago, Chile; Université Grenoble Alpes, CNRS, IPAG, France]
• Hughes, A. Meredith [Wesleyan University, Middletown, USA]
• Öberg, Karin I. [Harvard-Smithsonian Center for Astrophysics, Massachusetts, USA]
• Ricci, Luca [California State University, Northridge, USA]

Planetary systems form in the discs of gas and dust that orbit young stars. In the past few years, observations of these discs at (sub-)millimetre wavelengths with very fine angular resolution have started to uncover the hallmarks of small-scale substructures in the spatial distributions of their pebble-sized particles. These are some of the fundamental signatures of the planet formation epoch, since they trace localised concentrations of material that facilitate the formation of much larger planetary building blocks, and may themselves be created by young planets interacting with their birth environments.