Why Large Stars don’t last as Long as Small Stars

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"Why Large Stars don't last as Long as Small Stars"
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The birth and the death of a star remain a highly debated topic among those who are interested in the subject, although new technologies and centuries of research have given scientists a considerable amount of knowledge. It is such knowledge that could be used to unravel the mystery of why large stars fail to last longer than much smaller stars. This article will therefore discuss the life stages of large and small stars in order to reason out why the large stars won't last longer than the smaller ones.

What is a star?

Stars can be described as ‘hot bodies’ which consist of glowing gases and a core where nuclear fusion gives rise to enormous amounts of energy. Stars are also described in terms of how they compare with the Sun and, according to scientists, a star can be 450 times smaller or 1,000 times larger than the diameter of the Sun. Similarly, the surface of stars can have a temperature between 3,000 and 50,000 degrees Celsius. The enormous amount of energy produced by the star could give rise to its color, and the stars which are considered hottest appear in blue, while the coolest stars appear in red. However, stars with surface temperatures such as that of the Sun would appear yellow.

What is the definition used to describe ‘small’ and ‘large’ stars?

In general, smaller stars are considered as having one and a half times the mass of the Sun while the larger stars are considered to be those having at least three times the mass of the Sun.

What are the terminal stages of a star?

With regard to smaller stars, their mass can remain intact for about 10 billion years, until all their hydrogen is fused to form helium. As the core contracts, there will be reactions taking place around the core, while the helium would fuse to form carbon. Thus, the outer layers of the core begin to expand while becoming cooler and less bright, giving rise to a ‘red giant.’ As the helium core runs out, the outer layer is said to drift away from the core and therefore gives rise to the final stages of the star, which are known as ‘white dwarf’ and ‘black dwarf’ stages.

In relation to massive stars, the same process can be counted in millions of years instead of billions of years, as was the case with smaller stars. Thus, the time it takes for a massive star to enter its termination path would be much shorter. However, it will follow the same path of ‘burning out’ as with smaller stars although, at one particular point, there would be a massive collapse in the core, which will give rise to a phenomenon known as a ‘supernova’ explosion. If the core somehow survives the explosion and remains around 1.5 to 3 times the Suns mass, it will become a tiny, very dense ‘neutron star,’ while a much larger remnant core could contract to become what is known as a ‘black hole.’

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