The Galactic Core refers to the dense, star-cloud at the center of the galaxy. It is approximately 7000 light years in diameter and its nucleus is nearly 30,000 light years from Known Space.[1]
It was discovered by the Puppeteers to be undergoing a cataclysmic explosion, caused by a chain reaction of supernovae, sending out waves of deadly radiation that will engulf Known Space in approximately 20,000 years.[1]