How are black holes made?
Black holes are born out of the deaths of massive stars
1 Nebula
These are giant clouds of dust and hydrogen and helium gases. Clumps of a nebula subjected to the influence of gravity, radiation and temperature form a hot, independent core. This takes 100,000 years. 2 Yellow dwarf
An average yellow G-type mainsequence star like our Sun will form, and through nuclear fusion will burn up its central core of hydrogen and helium. Their life span is about 10 billion years. 3 Red giant
As hydrogen fuel is used up in the core of a star, hydrogen burning occurs outside the core, causing the star to expand to hundreds of times its original size. The life of a red giant lasts around 1 billion years. 4 Planetary nebula
In the last stages of the life of a red giant, its huge shell of gas and dust – containing elements of nitrogen, neon, oxygen, carbon and helium – is ejected, forming a planetary nebula. 5 White dwarf
The remaining core of a red giant, stripped of its outer layers, is now designated a white dwarf. Its volume might be the size of Earth, but it will have a mass equal to our Sun. The core is very hot. 6 Black dwarf
It’s been calculated that it will take tens or even hundreds of billions of years before a white dwarf will have expended all its energy to become a dim black dwarf. 7 Blue star
These are hot and massive O-type stars, usually located in the spiral arms of galaxies or in congested multi-star systems. Their life span is around 10 million years.
8 Red supergiant
As the hydrogen and helium at the core are burnt off in large stars – those 10 to 40 times the size of our Sun – outer layers expand at a rapid rate. They have a life span of a few million years.
9 Supernova
This is the gigantic explosion caused when a supergiant runs out of fuel. Within a few seconds the mass is crushed towards its core, resulting in shock waves that trigger the explosion of its outer layers.
10 Neutron star
A neutron star is incredibly dense – gravity is an astonishing 200 billion times that of Earth’s. One tablespoon of a neutron star is equivalent to the weight of Everest.
11 Black hole
The explosive power of a supernova can produce a black hole at its core. Its gravity is so powerful that even light cannot escape it, and it distorts the spacetime continuum with its immense mass.