Black holes are some of the strangest and most fascinating objects in the universe. They're extremely dense, with gravitational forces so strong, that nothing, not even lights, can escape once it crosses the boundary known as the event horizon.
The Milky Way could contain over 100 million black holes, though detecting these gluttonous beasts is very difficult. At the heart of the Milky Way lies a supermassive black hole — Sagittarius A*. The colossal structure is about 4 million times the mass of the sun and lies approximately 26,000 light-years away from Earth, according to a statement from NASA.
