SAGITTARIUS A* : THE BLACK HOLE OF MILKY WAY .

In a paper published on October 13,2018,the  discovery of conclusive evidence that Sagittarius A* is a black hole was announced.

Sagittarius A* is a bright very compact astronomical radio source at the centre of the Milky Way,near the border of the constellation Sagittarius and Scorpio about 5.6°south of the ecliptic. It is the location of a supermassive black hole,similar to those Generally accepted to be at the centre of most if not all spiral and elliptical galaxies. 

Observation of a number of stars orbiting around Sagittarius A*,most notable the star S2,have been used to provide evidence for the presence of, and produced data about ,the Milky Way's hypothesized Central supermassive black hole.

THE BLACK HOLE OBSERVATION AND DESCRIPTION BY SCIENTIST.

 Astronomers have been unable to observe SGR A*in the optical spectrum because of the effect of 25 magnitudes of extinction by dust and gas between the source and Earth. Several teams of researchers have attempted to image SGR A* in the radio spectrum using very long baseline interferometry (VLBI).

At the Distance of 26,000 light-year this yields a diameter of 60 million kilometers.For comparison, Earth is 150 million kilometres from the sun and Mercury is 46 million kilometres from the sun at perihelion .The proper motion of SGR A* is approximately 2.70 mas per year for the right ascension for the declination. 

In 2017,direct radio images were taken of sagittarius A* and M87*by the Event Horizon Telescope. 

THAT'S ALL FOR TODAY. 

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