The stars have amazed humanity since ancient times, when thousands of years ago man observed the heavens and asked many questions. Today we still find it a very interesting phenomenon, but have you ever really wondered: what is a star and why do they shine?
A star is basically a large plasma ball composed of hydrogen and helium, with a mass capable of sustaining nuclear fusion in its nucleus. The stars conform and condition the galaxies, but think nothing else about ours, the Milky Way and its relationship with the Sun. For these reasons, studying the stars is a fundamental point for the sciences and especially for astronomy, as does and as NASA points out.
The stars shine because they are a huge nuclear reactor where there is a lot, but really very hot. At the center of these, there are atoms constantly separating as a result of giant atomic collisions that convert the hydrogen atoms into helium atoms and finally release a large amount of energy.
That energy causes the star to have extremely high temperatures and to shine. The complete reaction is called nuclear fusion, as the nuclei of the atoms fuse to form a new and heavier nucleus. During the same matter is not preserved, it takes a plasma state, because much of it is transformed into energy.
And God made the two great lights, the greater light to rule the day, and the lesser light to rule the night: he also made the stars.
(Genesis 1:16)