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Various Planets and Satellites in Solar System-Stars

Stars can be described as a luminous extra-terrestrial body of hot air or gas containing helium and hydrogen. Stars are located far away in the universe, and the nearest star is more than hundreds of light-years away. Light-year can be described as the distance that light travels within a year, i.e. approximately 9.5 trillion km. From planet earth, the nearest star is the Sun. The temperature of stars is severely hot, and because of this, a fusion of several elements occurs inside the stars. Hence, the reason why these stars shine even from a few light-years away. 

What is a Star?

Based on the astrophysical definition, it can be described that stars are enormous glowing extra-terrestrial bodies that mostly contain gas. The stars are located far away in the universe, and the nearest star is more than hundreds of light-years away. Light-year can be described as the distance that light travels within a year, approximately 9.5 trillion km. From planet earth, the nearest star is the Sun. 

The temperature of stars is severely hot, and because of this, a fusion of several elements occurs inside the stars. Hence, the reason why these stars shine even from a few light-years away. The shine or glow of the stars also depends on the temperature. The stars that emit bluish light are extremely hot compared to others. On the other hand, the stars that emit a reddish hue have significantly cooled down compared to others. These smallest stars in the universe are commonly called “red dwarfs”. 

How are stars created and the timeframe?

The stars are formed by dust and gas accumulation, then the accumulation collapses mainly due to gravitational pressure, and this is how stars are formed or born. The overall process of formation usually takes an average time of million years. The time to accumulate the dust and gas in the initial stage till the formation of these glowing bodies is quite a long process. It can be mentioned that all the stars are results of gravity compressing atoms and creating fusion. 

After the birth of a star, there is enough leftover material, mostly used to create other objects such as planets. The formation of stars is quite difficult to observe as the dust particles that create the stars are not visible. However, this formation process can be viewed with the help of radio waves and radio telescopes. 

The temperature of stars and how do they die? 

The hottest star in the universe has an approximate temperature of 210,000 K, and the name of that star is “Wolf-Rayet”. Moreover, the colour or the glow of the stars depends on the star’s temperature. The brightest stars usually have high temperatures and emit a bluish light. On the other hand, the stars that emit a reddish hue are usually quite cold. In the universe, the most common stars are the red dwarfs, which emit red light. These kinds of stars usually have a temperature of 35,000 Kelvin. 

The lifespan of stars mainly depends on the temperature. The stars, which usually have low temperatures, have less lifespan than others. The Sun is also a star, and the remaining lifespan of the Sun is nearly 12 billion generations. The red dwarfs are quite weak and have a lifespan between 4 billion to 7 billion years. The brightest stars have a lifespan of 10 trillion ages. 

Conclusion

It can be concluded that stars are quite important in the universe. Even the Sun under which the planet Earth is dependent is also a star. The accumulation of dust and gas usually creates the stars, and it is considered a massive glowing extra-terrestrial body that mainly contains gas. The reasons for stars shining involve radiation that originated from the internal energy of the stars. The gravitational force is mainly responsible for creating the fusion within the elements, and the stars glow due to the brightness. The temperature of stars is severely hot, and because of this, a fusion of several elements occurs inside the stars. Hence, the reason why these stars shine even from a few light-years away. The shine or glow of the stars also depends on the temperature. The stars that emit bluish light are extremely hot compared to others. On the other hand, the stars that emit a reddish hue have significantly cooled down compared to others. 

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What do you mean by a star?

Ans. Based on the astrophysical definition, it can be described that stars are enormous glowing extra-terrestrial bo...Read full

How are stars formed or born?

Ans. The stars are formed by dust and gas accumulation, then the accumulation collapses mainly due to gravitational ...Read full

The lifespan of a star?

Ans. The overall process of formation usually takes an average time of million years. The time to accumulate the dus...Read full

What is the temperature of stars?

Ans. The hottest star in the universe has an approximate temperature of 210,000 K, and the name of that star is “Wolf-Rayet”. In the un...Read full

How do the stars die?

Ans. Stars usually die, or the glow is diminished when the nuclear fuel is exhausted, and the temperature is no long...Read full