Discovery of Sagittarius A*
February 1974 · 20th Century
On February 13 and 15, 1974, astronomers Bruce Balick and Robert L. Brown discovered a bright, compact radio source at the center of the Milky Way galaxy using the baseline interferometer of the National Radio Astronomy Observatory in Green Bank, West Virginia. This object would later be named Sagittarius A* and confirmed to be a supermassive black hole with a mass of approximately 4.3 million times that of our Sun.
Key Figures
Bruce BalickRobert L. Brown
Locations
Sagittarius A*National Radio Astronomy Observatory
Topics
Milky Wayradio astronomyblack holesspace explorationWest Virginia
Connected Events — 2 Connections
Balick and Brown's 1974 radio detection of Sgr A* confirmed the supermassive black hole at the center of the Milky Way, revealing the gravitational anchor around which the galaxy formed Formation of Milky Way Galaxy
The Event Horizon Telescope's 2022 image visually confirmed what Balick and Brown detected via radio waves in 1974, providing direct evidence of the supermassive black hole's event horizon First Image of Sagittarius A*
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