Big bang theory has always been interesting yet mystifying. The big bang theory was basically an attempt made by astronomers to explain how our universe came into being. So what actually does the word universe talk about? Universe includes anything and everything we call matter. It consists of the sun, moon, galaxies, stars, atoms, molecules and what not. A study says there are around 100 billion galaxies in the universe. But surprisingly the universe consists only about 10% of matter and 90% of dark space. Dark space is referred to the mass that does not emit or absorb electromagnetic radiations.
So how did all this come into existence? The Big Bang theory says it all started some 14 billion years ago. Universe was in the form of a very minute particle (like an atom) with a diameter of few millimeters and was very much hot and dense. Some say that this atom was so hot that it exploded at one point of time paving way for the creation of universe while others believe that there wasn’t any ‘explosion’ but an ‘expansion’ from the size of a tiny matter to the universe where we live today. The fact is that there has happened an expansion and is said to happen even today.
The stars are thought to have been born a few hundred million years after the big bang. A gigantic collection of stars, gases and dust is a galaxy. There are about billions of galaxies in the universe. Our earth is in the galaxy called Milky Way. The movement of galaxies away from our milky way at a considerable speed proves that expansion is still going on.
In the year 1963, two American scientists Arno Penzias and Robert Wilson discovered that microwave radiations fall to earth from the space. These were termed as CMB (cosmic microwave background) radiations. These radiations confirm the big bang theory. As light travels at a finite speed and takes lot of years to reach the earth, astronomers working on the light emitted from the space are actually working in the past. The CMB radiation was found to be emitted 13.7 billion years ago. Thus, by studying the detailed physical properties of the radiation, we can learn about conditions in the universe on very large scales at very early times, since the radiation we see today has traveled over such a large distance. Every hour the universe is said to expand by a billion miles in all directions. So what would be the fate of the universe is what the astronomers are working on.
Big Bang Theory: Explanation in simple words.
The big bang theory was basically an attempt made by astronomers to explain how our universe came into being.