| The Kepler mission revealed thousands of diverse planetary systems, and one goal of exoplanet research is a predictive theory that relates conditions of planet formation in a protoplanetary disk to those varied outcomes. Spatial scale, however, is an impediment to progress: at the distance of the nearest star-forming regions, the inner disks corresponding to the orbits of Kepler planets are usually unresolved, even by ALMA. Moreover, most of the mass in the inner disk appears to be rapidly accreted into larger objects that emit little compared to dust. Fortunately, photometric space surveys such as Kepler/K2 and now TESS enable a temporal exploration of inner disks via occultations of the central star by dusty structures, a phenomenon first described among some higher-mass Herbig Ae/Be stars (UXOrs) and extended by these surveys to solar-mass T Tauri stars ("dippers"). The mechanism(s) behind "dipping" is not definitely established, but observations underway could soon discern between alternative explanations such as disk warps, dusty winds, or evaporating planetesimals. Studies of the grain size, composition, and spatial distribution of the dust, as well as any accompanying gas, will help us trace the subsequent, hitherto hidden steps of planet formation. |