Disruption of the Orion molecular core 1 by wind from the massive star θ1 Orionis C

16 pags., 9 figs., 1 tab.Massive stars inject mechanical and radiative energy into the surrounding environment, which stirs it up, heats the gas, produces cloud and intercloud phases in the interstellar medium, and disrupts molecular clouds (the birth sites of new stars). Stellar winds, supernova explosions and ionization by ultraviolet photons control the lifetimes of molecular clouds. Theoretical studies predict that momentum injection by radiation should dominate that by stellar winds, but this has been difficult to assess observationally. Velocity-resolved large-scale images in the fine-structure line of ionized carbon ([C ii]) provide an observational diagnostic for the radiative energy input and the dynamics of the interstellar medium around massive stars. Here we report observations of a one-square-degree region (about 7 parsecs in diameter) of Orion molecular core 1—the region nearest to Earth that exhibits massive-star formation—at a resolution of 16 arcseconds (0.03 parsecs) in the [C ii] line at 1.9 terahertz (158 micrometres). The results reveal that the stellar wind originating from the massive star θ Orionis C has swept up the surrounding material to create a ‘bubble’ roughly four parsecs in diameter with a 2,600-solar-mass shell, which is expanding at 13 kilometres per second. This finding demonstrates that the mechanical energy from the stellar wind is converted very efficiently into kinetic energy of the shell and causes more disruption of the Orion molecular core 1 than do photo-ionization and evaporation or future supernova explosions.We acknowledge the work during the upGREAT squaredegree survey of Orion of the USRA and NASA staff of the Armstrong Flight Research Center in Palmdale and of the Ames Research Center in Mountain View, and the Deutsches SOFIA Institut. Research on the interstellar medium at Leiden Observatory is supported through a Spinoza award. We thank the ERC and the Spanish MCIU for funding support under grants ERC-2013-Syg 610256 Universities Space Research Association-NANOCOSMOS and AYA2017-85111-P, respectively