Princeton University Astrophysical Sciences 2017 Spitzer Lecturer - Lecture 1

ADDED - The circumstellar disks that naturally arise from the star formation process are the sites where planets are made. According to standard theory, tiny interstellar dust grains in these disks collide, stick and grow into kilometer-sized planetesimals that agglomerate into giant planets cores and rocky planets. Millimeter interferometry provides direct access to the cool constituents of these disks, with the revolutionary sensitivity and angular resolution of the Atacama Large Millimeter/submillimeter Array (ALMA) able to reach to the scale of Earth-like orbits around nearby pre-main-sequence stars. In this talk, I will discuss what we are learning from millimeter observations of thermal continuum emission from disk solids, including demographic trends, evidence for growth to pebble sizes, signatures of radial drift, the trapping of solids in ring-like "transition" disks, and the detection of substructures whose origin remains to be fully explained.