SagittariusA

the Sagittairus A star system, at galactic core of the Milky Way

Despite the astronomical observations already made of Sagittarius A, it remained a hotly contested debate as to how this small star could have warped the entire galaxy to form as a spiral being pulled ever inward toward it. It simply didn't have enough gravity to account for the effect. In the late 1990's physicist Stephen Hawking proposed the theory of "black holes" or imploded stars. In 1999, an announcement was made by NASA that "black holes" likely existed at the centre of all spiral galaxies, including our own Milky Way. Only a "black hole" could account for the massive gravity needed to form a galaxy.

Here is an artist's depiction, again from NASA, of a black hole. Notice that the poles of the black hole, operative at 90° from the "accretion disk" surrounding its equator, project "gas jets" above and below. These "gas jets" have been analysed and found to contain elements that are, terrestrially, metallic. Within these clouds of iron have also been measured photons that are travelling faster than the predicted speed of light in a vaccuum, which Einstein called "c" in his famous equation: E=Mc^2.