Title: Star Formation and Feedback in the Orion Complex

Speaker: Professor John Bally (University of Colorado Boulder)

Time: 14:00pm, October 10, 2025

Location: 5-516, PMO Xianlin Campus

Abstract: The Orion star forming complex (distance~400 pc) is the nearest site of both low- and high-mass star birth. I will review the "ecology" star formation in Orion from individual stars to the ~300 pc Orion-Eridanus super-bubble using results from the CARMA/NRO CO survey, ALMA, and multi-epoch HST and JWST studies. Forming stars produce time-variable jets, winds, and outflows that provide evidence for accretion bursts, N-body interactions, and in some cases protostellar mergers.  A ~10^48 erg explosion in Orion OMC1 ~550 years ago (that is when the light reached Earth) was powered by an N-body interaction which produced a compact binary or stellar merger and ejected three runaway stars. Feedback (UV, winds, supernovae, etc.) and N-body dynamics are crucial ingredients in establishing stellar masses and the IMF and sculpting of the interstellar medium (ISM) from Solar System to super-bubble scales.