Throughout history, it has been the effort of man to explain the beginning of the universe. Different hypotheses were propounded in this regard and were discredited as new discoveries were made from time to time.
However, it is true that the early explanation showed the little scientific awareness. Human knowledge was replaced by myths and legends. Different countries and religions had their own perception of the beginning of the universe which differed from one another.
With the invention of scientific tools for observation, measurement and calculation, man has achieved partial success in probing the mysteries of the vast and immeasurable universe.
During the past few hundred years man could have at his disposal telescopes, cameras, highly sophisticated computers and above all, space vehicles for the actual probing of the deep space. It is, however, true that despite all the technological advances, man has failed to know exactly as to how the universe originated.
Several theories have been propounded about the origin of the universe, but no theory proves to be infallible.
The Big-Bang theory, also called the ‘Expanding Universe Hypothesis’, developed by Edwin Hubble in 1920, Hoyle’s concept of ‘Steady State’, and ‘the Theory of Oscillating Universe’ are some such theories which tried to explain the mysteries of the universe, but all of them seem to be mere conjectures, far from the reality.
Despite his failure to ascertain the way universe originated, man has been able to learn a good deal about its mysteries. Now, it has been discovered that there are millions of galaxies similar to the Milky Way of which our solar system is a tiny part.
It is now a well-known fact that there are billions of stars like our sun, and that there are many other solar systems with their planets and moons.
Furthermore, it has also been estimated that in our galaxy or the Milky Way alone there may be about a million planets that are most probably inhabited by intelligent people like our planet earth.