Astronomy & Space Science · AST-507
The Galactic Center & Sagittarius A*: Structures & Vocabulary
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Structure
Structure of The Galactic Center & Sagittarius A*
The Galactic center contains the nuclear star cluster surrounding Sagittarius A*, stars on tightly bound orbits, streams of ionized gas, and nearby molecular clouds. Interstellar dust heavily obscures the region in visible light, so infrared, radio, X-ray, and submillimeter observations are essential.
Evidence behind this section3 claims
At the dynamical center of the Milky Way lies Sagittarius A*, a compact radio source associated with a supermassive black hole of roughly four million solar masses. supported
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- 01The Milky Way Galaxy — SummaryOpen source ↗
OpenStax Astronomy 2e
View claim-by-claim traceability3 verified claims
At the dynamical center of the Milky Way lies Sagittarius A*, a compact radio source associated with a supermassive black hole of roughly four million solar masses.
supported · checked Sep 22, 2026Decades of infrared astrometry track individual stars completing fast elliptical orbits around an unseen compact mass.
supported · checked Sep 22, 2026Stars orbit the central mass under strong gravity, while gas falling inward can heat and radiate before reaching the black hole.
supported · checked Sep 22, 2026