Shapley Center

The galactic core, also referred to as the Shapley Center, is an area of intense radiation and gravity that spreads out for thousands of light-years in the center of the galaxy. The central core is the center of the spiral shape of the galactic region, where all the spiral arms meet in what is presumed to be a large collapsed black hole-type mass referred to as Sagittarius A*. This region is considered by astronomers and astrophysicists as the origin of star formation. 

In 2269, the USS Enterprise (NCC-1701) passed approached the galactic core, where the crew encountered the satyr being Lucien, and later an inter-dimensional gate to the planet Megas-Tu. 

Until 2287, the technology of the Federation was insufficient to probe into the energy mass which came to be known as the Great Barrier.