Stars are bright celestial objects which give out light of their own. A star is formed from a giant, slowly rotating cloud called nebula which is made up entirely or almost entirely of hydrogen and helium. Due to its own gravitational pull, the cloud begins to collapse inward, and begins to shrink. As it shrinks, it spins more and more quickly, with the outer parts becoming a disk while the innermost parts become a roughly spherical clump. This collapsing material grows hotter and denser, forming a ball-shaped ' Protostar '.When the heat and pressure in the Protostar reaches about 1.8 million degrees F (1 million degrees C), the atomic nuclei that normally repel each other start fusing together, and the star ignites. Nuclear fusion converts a small amount of the mass of these atoms into extraordinary amounts of energy — for instance, 1 gram of mass converted entirely to energy would be equal to an explosion of roughly 22,000 tons of TNT.
This is like an atom bomb explosion, the difference is that in these weapons the atomic nucleus splits to release energy whereas in stars the nuclei fuse to form energy. Nuclear fusion is much more powerful than nuclear fission.
The reaction happening in a star has immense power, if measured in watts, our sun's luminosity is 400 trillion trillion watts, the luminosity of a star is usually measured in terms of the luminosity of the sun. For example, Alpha Centauri - the closest star after sun - is about 1.3 times as luminous as the sun.
The size of a star is very huge and cannot be measured in meters or even kilometers, therefore they are measured relative to the size of our sun. Stars range in size from neutron stars, which can be only 12 miles (20 kilometers) wide, to supergiants roughly 1,000 times the diameter of the sun.
The sun and other stars are the supporters and giver of life. The life that thrives on planet earth is pretty much because of the existence of sun. The heat from the sun is essential for our survival. All kinds of sources of energy - food, fossil fuels, wind energy, tidal energy, etc. - are primarly derived from sun. The constituents of our body like proteins, carbohydrate, amino acids cannot be formed without sunlight. It is the sun's gravitational pull that supports the solar system. In the end it would be fair to say that if sun dies (its expected life is more 5.5 million years, so don't be afraid) we all will be killed too.
This is like an atom bomb explosion, the difference is that in these weapons the atomic nucleus splits to release energy whereas in stars the nuclei fuse to form energy. Nuclear fusion is much more powerful than nuclear fission.
The size of a star is very huge and cannot be measured in meters or even kilometers, therefore they are measured relative to the size of our sun. Stars range in size from neutron stars, which can be only 12 miles (20 kilometers) wide, to supergiants roughly 1,000 times the diameter of the sun.
The sun and other stars are the supporters and giver of life. The life that thrives on planet earth is pretty much because of the existence of sun. The heat from the sun is essential for our survival. All kinds of sources of energy - food, fossil fuels, wind energy, tidal energy, etc. - are primarly derived from sun. The constituents of our body like proteins, carbohydrate, amino acids cannot be formed without sunlight. It is the sun's gravitational pull that supports the solar system. In the end it would be fair to say that if sun dies (its expected life is more 5.5 million years, so don't be afraid) we all will be killed too.
No comments:
Post a Comment