Sagittarius A

Sgr A and environs, as seen at 90 cm wavelength by the Very Large Array
Sagittarius A
Observation data
Epoch J2000      Equinox J2000
Constellation Sagittarius
Right ascension 17h 45m 40.0409s [1]
Declination −29° 00′ 28.118″ [1]
Astrometry
Radial velocity (Rv)46 km/s
Details
Mass~4.1 million M
Radius31.6 R
Age+10.000 years
Other designations
AX J1745.6-2900, SAGITTARIUS A, W 24, Cul 1742-28, SGR A, [DGW65] 96, EQ 1742-28, RORF 1742-289, [SKM2002] 28.
Database references
SIMBADdata

Sagittarius A (Sgr A) is a complex radio source at the center of the Milky Way, which contains a supermassive black hole. It is located between Scorpius and Sagittarius, and is hidden from view at optical wavelengths by large clouds of cosmic dust in the spiral arms of the Milky Way. The dust lane that obscures the Galactic Center from a vantage point around the Sun causes the Great Rift through the bright bulge of the galaxy.

The radio source consists of three components: the supernova remnant Sagittarius A East, the spiral structure Sagittarius A West, and a very bright compact radio source at the center of the spiral, Sagittarius A* (read "A-star"). These three overlap: Sagittarius A East is the largest, West appears off-center within East, and A* is at the center of West.

  1. ^ a b Cite error: The named reference Reidetal was invoked but never defined (see the help page).