Environmental interactions: A paradigm shift in planet formation

by Dr Ashish Gupta (University of Virginia, USA)

Wednesday 11 Feb 2026, 14:30 → 15:30 Asia/Kolkata

AG-80

Planet formation is generally studied in the context of isolated disks around young stars. However, we know that these disks are moving within large-scale molecular clouds and simulations show that they continue to accrete material from them throughout their lifetime. Interestingly, several trails of infalling gas, often referred to as streamers, have been recently detected around planet-forming disks. To quantify their impact, we developed TIPSY (Trajectory of Infalling Particles in Streamers around Young stars), a first-of-its-kind code to model their dynamics. TIPSY analyses reveal that streamers can greatly increase the mass budget available to form planets. Moreover, comparison of angular momentum of streamers and disks show they can easily misalign disks, which can leave imprints on the planetary systems they form. Furthermore, results from ALMA large-program DECO (Disk-Exoplanet C/Onnection) show that nearly half of these disks are undergoing late-stage infall of material at a given time. Together, these findings demonstrate that the star-forming environments can drastically affect the evolution of planet-forming disks and thus, the formation of planets.