This was the name of the compact radio source
detected at the black hole's position; the * emphasizes its unusual nature.
The brightness temperature for a compact radio source
is given by (e.g., )
Moreover, this change in speed is directed toward a compact radio source
, called Sagittarius A*, that lies at the presumed location of the black hole.
In recent years attention has focused on a compact radio source
called Sgr A* ('Sagittarius A star')....
In a separate study, researchers have for the first time directly detected infrared emissions from a compact radio source
, Sagittarius A*, which has been identified as a candidate for the black hole thought to lie at our galaxy's center.
Among specific topics are connections between jet parameters and black hole masses in quasars, where accretion disk around black holes end, the x-ray view of compact radio sources
, scientific highlights of the MAGIC collaboration observations of AGN, winds and outflows from supermassive black holes, and a dichotomy in radio jet orientation in elliptical galaxies.
The spectra were taken of previously identified compact radio sources
in the nearby spiral galaxy NGC 6946.
The team used the worldwide Very Long Baseline Array (VLBA) to measure the annual parallax shift of four compact radio sources
in the nebula.