A Black Hole is a celestial body whose gravitation is so immense that nothing can escape its influence, not even light. As we know now, there are plenty of them. The discovery is surely one of the greatest advances in the last ten years. They were predicted by theory which is a crowning achievement for Mankind. Surprisingly, the history of the discovery goes way back in history. But because they are black they are hard to see and to detect. Since the discovery of a supermassive Black Hole in the centre of the Milky Way, such objects have been discovered in nearly all galaxies. Only now are we beginning to understand just how closely the formation and the destiny of galaxies are influenced by black holes.
Our Milky Way with the bright centre concealing a Black Hole
(By courtesy of the European Southern Observatory, ESO)
It is possible that human beings could not exist without them. They attract, in a double sense of the word. On one hand they attract matter because of their immense gravity and on the other hand they are attractive to Scientists and non-Scientists alike because of the many secrets which accompany their existence.
They certainly do exist out there in space. They have now entered every day language. Something which disappears and can‘t be found is said to have "disappeared into a black hole". It is a saying which can be heard in daily speech and has become a euphemism for something which gets lost for ever.
So, to where does all the poor unfortunate prey of a Black Hole go? Victims come in all sizes, sometimes consisting of complete sun systems including their planets and sometimes even whole galaxies are eaten up by the monster, step by step. Black holes are frightening!
Pre-occupation with the subject soon leads us to the fundamental questions of Mankind: Where do we come from? Where are we going?
The Astrophysicist gives some surprising answers. This is now becoming possible because of large-scale projects like the Large Hadron Accelerator in Geneva and by big telescopes like the "Very Large Telescope" of the ESO in Chile.