Milky Way, Radius The Milky Way is about 1,000,000,000,000,000,000 km ( about 100,000 light years or about 30 kpc) across. The Sun does not lie near the center of our Galaxy. read more
The black hole system at the centre of our galaxy is known as Sagittarius A* housed within a radio source. It has a mass of around 4–5 million solar masses and a radius of around 2 x 10^7 km, or 20 times that of our own sun. read more
The Milky Way is the second-largest galaxy in the Local Group, with its stellar disk approximately 100,000 ly (30 kpc) in diameter and, on average, approximately 1,000 ly (0.3 kpc) thick. read more