Introduction
If one was to consider a star that shines ever so brightly in the sky, it is quite ironic to see that the center of many fairy tales is actually nothing more than a ball of plasma that is held together because of its own gravity and is luminous (Burrow, 1857). The only reason because of which we cannot see a star in the day is because the sun does not allow us to see them. The sun is not present in the night to outshine the countless stars in the sky and it is for the same reason that we can see them in the night.
Main body
It was previously believed by astronomers throughout the world that stars were formed as a result of enormous clouds of gas that came together with large amounts of dust and hydrogen and these stars were known as nebulae. In cases where this cloud became too big then there is a possibility that the strong gravity of the star overcomes the gas pressure of the nebulae and this causes the cloud to suffer a collapse. Once the process of fusion has initiated the outer layer of the gas get blown away as a result of the ceasing of the contractions (Wills & Anderson, 2001). There is nothing more than a bright ball that constitutes of hydrogen that is left remaining as a result of the continuously executing fusion reactions in the core. This is what is commonly referred to as a star.
A protostar is actually a point that comes in the evolution of a young newborn star that comes only once the young star has undergone fragmentation before the star can collapse. It is at this point that the mass of the star becomes integral because the fusion process could last for as long as less than ten million years.
The mass of the star determines the number of years that the process takes. The initial mass only serves to establish the life stages of the star and the death that the star can be expected to experience. In its initial stages, the star can exist as either a massive star, or a star no larger than average size.
The amount of time that the star spends going through each phase of its life is called put together is referred to as the main sequence. It is therefore no surprise that most of the stars that one sees in the sky are going through their main sequence and it is over the time period of billions of years that the star the star manages to compensate for the sheer amount of head and light energy that it loses during the time when it shines bright. As a star shines bright, its temperature, density and pressure are subjected to a continuously climbing increase in the core region of the star as the contractions slowly continue (Clerke, 1905).
Conclusion
When the star reaches the end of its life, it enters a phase referred to as the planetary nebula where it becomes faint and invisible to the naked eye. Even though the core continues to shine, it remains what is referred to as a white dwarf. This is the final evolutionary stage of the star and it reaches an extremely low mass. Solar mass becomes an integral factor at this point.
References
Burrow, E. B. (1857). Sketches of astronomy; or, What are stars?: or, What are stars? Oxford University.
Clerke, A. M. (1905). The system of the stars. Adam & Charles Black.
Wills, S., & Anderson, J. (2001). Astronomy: Looking at the Stars. The Oliver Press, Inc.