galactic centre

astronomy

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June 29, 2026

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The galactic center of the Milky Way Galaxy is dominated by a supermassive black hole known as Sagittarius A* (Sgr A*). This black hole, located in the constellation Sagittarius, possesses a mass equivalent to about 4.3 million Suns.12

Direct observation of the galactic center is hindered by dust, making non-visual wavelengths like radio, infrared, X-ray, and gamma-ray crucial for study. Observations of stars orbiting Sgr A* provide evidence for its existence as a black hole. The Event Horizon Telescope has even imaged the shadow of this black hole against the surrounding hot gas.21

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galactic coordinate
Galactic latitude (denoted by the symbol b) is measured in degrees north or south of the Galaxy’s fundamental plane of symmetry. This plane is defined by the galactic equator, the great circle in the sky best fitting the plane of the Milky Way, as determined…
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Galactic latitude (denoted by the symbol b) is measured in degrees north or south of the Galaxy’s fundamental plane of symmetry. This plane is defined by the galactic equator, the great circle in the sky best fitting the plane of the Milky Way, as determined…
Read More

Milky Way Galaxy
Rotation
…at different distances from the centre of the Galaxy, the measured velocities of disk stars in different directions along the Milky Way exhibit different patterns. The Dutch astronomer Jan H. Oort first interpreted this effect in terms of galactic rotation motions, employing the radial velocities and proper motions of stars.…
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…at different distances from the centre of the Galaxy, the measured velocities of disk stars in different directions along the Milky Way exhibit different patterns. The Dutch astronomer Jan H. Oort first interpreted this effect in terms of galactic rotation motions, employing the radial velocities and proper motions of stars.…
Read More