Astronomers Confirm Milky Way's Black Hole Expels Wind

After half a century of searching, astrophysicists have found conclusive evidence of a powerful wind emanating from Sagittarius A* (Sgr A*), the supermassive black hole at the Milky Way's center. This landmark discovery confirms long-held theories that black holes, while known for consuming matter, also expel it as winds or jets due to the immense energy generated during accretion.

Observing Sgr A* presents extreme technical difficulties. Astronomers must peer through the galaxy's plane, which is obscured by gas, dust, and ionized structures. While past evidence of Sgr A*'s past eruptions existed, detecting current outflows had remained elusive. Researchers believe the black hole is currently in a quieter phase, making it incredibly hard to observe.

Utilizing five years of deep observations from the Atacama Large Millimeter/Submillimeter Array (ALMA) in Chile, the team generated the clearest image to date of the cold molecular gas surrounding the black hole. This image captured gas extremely close to Sgr A*, within a parsec distance. By applying a new calibration technique to filter out the black hole's bright radio signals, they achieved an unprecedentedly sharp and deep view, revealing the long-sought evidence of its expelled wind.

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To observe our own black hole, we have to look through the plane of our galaxy. That means we have to look through gas, dust and ionized structures, and one cannot really see through all of that easily.