Black Holes are objects with such immense gravitational fields that nothing can escape from its attraction, including light. Black Holes range in size from as low as few solar masses (e.g. V4641 Sgr), to billions of solar masses (e.g. at the center of our Milky Way galaxy). Now for the first time, the birth of a Black Hole has been captured. According to Neil Gehrels of NASA, the Swift orbiting observatory detected the Gamma Ray Burst of the collision between two dense Neutron Stars (stars composed entirely of neutrons), which combined to create a Black Hole.

Swift Observatory (Courtesy: MSSL)Gamma Ray Bursts (GRB) are the most enigmatic events in the universe. These bursts release stupendous amounts of energy (equivalent to our Sun's total energy output over its life-time) in a fraction of a second. So powerful are these blasts, that if one were to occur within 6000 light years, life on Earth might be threatened!
The GRB created by the collision was seen across the whole universe. The satellite recorded the x-rays from the collision, but the visible light was too faint to be detected by the satellite. But ground-based telescopes were able to see the aftermath of the collision. The collision matched what theorists had predicted would happen when two neutron stars collide, helping solve a 30 year old mystery.