Only on KBears.com, by the Knowledge Bears
Our Sun is A Star:
A White Dwarf is What Stars can become:
Pictures Courtesy of NASA/JPL
|Stars begin as
clouds of dust and gas in a concentrated area within a galaxy known
As more hydrogen is pulled into the cloud by gravity, the cloud begins to spin.
As the cloud begins to spin faster, the atoms of hydrogen start bumping into each other causing nuclear fusion.
This fusion is the main source of heat in a star.
This heated gas, in turn, creates a glow that classifies the cloud as a proton star.
As the proton star evolves, it grows and gains mass.
When it is finished growing, it is called a main sequence star.
A main sequence star can shine for millions of years or more.
The amount of time a main sequence star lives is determined by how big it is.
Medium size stars begin to use up their fuel until its gravity pulls it mass inward becoming small and compact, sometimes only a few kilometers across.
This star is called a "white dwarf" and can remain this way for a long time.
White dwarfs shine with white hot light until they finally burn out and will remain a "black dwarf".
In larger stars the process of nuclear fusion is greater and forms iron at the star's core.
The iron core then acts like a sponge, soaking up energy from the surrounding cloud.
Eventually, all this condensed energy is released and generates a massive explosion called a supernova.
After a supernova, the matter at the center of the star becomes a neutron star or a black hole.
Smaller stars become neutron stars, but larger stars collapse inward because of their gravity and become black holes.