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arXiv · 2509.10615

The Discovery of an Active Wind from the Milky Way's Black Hole

Mark D. Gorski·Elena Murchikova
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Abstract

Every large galaxy has a black hole in its center. The interaction between the black hole and its host profoundly shapes galactic evolution and the Universe as a whole. The key features of this interaction are black hole jets -- or more generally, winds -- which every black hole must have. Despite the proximity and importance of our Galaxy's central black hole, Sagittarius A* (Sgr A*), the active wind from it has eluded scientists for over half a century. Here we report the discovery of a large active wind from Sgr A* using unprecedentedly deep (T$_b \sim30$ mK) and high angular resolution (<0.25") observations with the Atacama Large Millimeter/Submillimeter Array (ALMA). We detect a large conical clearing in the cold molecular gas surrounding Sgr A* that is at least 1~parsec long and has a ~45 degree opening angle. The morphology and energetics of this structure are consistent with active clearing of gas by a hot wind from Sgr A*.

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Mark D. Gorski, Elena Murchikova. 2026-06-04. The Discovery of an Active Wind from the Milky Way's Black Hole. https://doi.org/10.3847/2041-8213%2Fae63cf

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