This “lake” is water floating around in a cloud surrounding a huge black hole- a quasar, actually. The water keeps being made, too. The black hole is creating it by knocking hydrogen and oxygen atoms together. Officially, NASA says the cloud contains 140 trillion times all the water in the world’s oceans.
Astronomers have discovered the largest known structure in the universe, a clump of active galactic cores that stretch 4 billion light-years from end to end. The structure is a light quasar group (LQG), a collection of extremely luminous Galactic Nuclei powered by supermassive central black holes.