Supernova and black holes – Higher tier
More massive stars than the Sun have a very different life cycle and follow the right hand path in the diagram above:
\(\begin{equation} \begin{aligned} Nebula \rightarrow protostar \rightarrow main~sequence~star \rightarrow \\ red~super~giant~star \rightarrow supernova \rightarrow \\ neutron~star, ~or~a~black~hole~(depending~on~size) \end{aligned}\end{equation}\)
After the main sequence period, they expand and become red super giants.
This is followed by an explosion in which the outer layers of the star are ejected.
This is called a supernova.
The star will shine as supernova for a relatively short period of time with the brightness of 10 billion suns.
After the supernova the remaining core of the star may collapse further.
Some become neutron stars while very massive ones become black holes.
An exploding supernova throws hot gas into space.
Neutron star or black hole
Depending on the mass at the start of its life, a supernova will leave behind either a neutron star or a black hole.
A black hole is anything but empty space.
Rather, it is a great amount of matter packed into a very small area.
A black hole is made when the centre of a very big star falls in upon itself, or collapses.
All the matter of the star becomes squeezed into a tiny space and the force of gravity increases greatly.
There is such a strong gravitational fieldThe space or area around a body where another body would experience gravitational attraction. in a black hole that nothing can escape from it, including electromagnetic radiation such as light.
Since no light can escape, it appears black, and hence the name black hole.