Finnish researchers have discovered the largest known black hole so far. This massive black hole is lurking in the middle of quasar OJ 287, about 3.5 billion light years away from the Earth. The discovery of Finnish scientists was published last in Astrophysical Journal by Mr. Mauri Valtonen

This recently discovered black hole has a really staggering size. It is estimated that the black hole has a size of 18 billion Suns. The huge black hole has its own satellite. A “little” black hole with a size of 100 million times the size of the Sun orbits the giant black hole.

Discovering giant black holes is not a job for restless scientists. It took 30 years for Finns to discover this monster black hole. During 30 years the Finnish scientists followed the brightness of OJ 287. Researchers found out that the amount of light coming from the quasar fluctuates in 12-year cycles. The fluctuation was explained with a theory of two black holes, one orbiting another. As the smaller black hole comes closer to OJ 287 every 12 years, the target becomes brighter.

The masses of these two black holes were calculated with the fluctuation of the amount of light. The explanation passed a critical test as it predicted accurately the latest time OJ 287 became brighter in last September.

There is one additional interesting thing related to this pair of black holes. The movement of the pair of black holes is related to Einstein’s theory of relativity, and by observing the changes of brightness of the target researchers can now test if Einstein’s theory of relativity applies in the gigantic gravity of black holes. This is the first time such a test can be arranged.

This news of the giant black hole is impressive. As astronomers know, it is very difficult to realize how big this universe is and how massive structures there are. Thinking about the size of this massive black hole (18 billion Suns) makes me quiet. I would somehow understand a size of 18 Suns or even 1800 Suns, but 18 billion is just too much. Even 18 million would be too difficult to realize. Anyhow, this is why I love astronomy. Everything out there is so huge. Awesome.