Our universe is very large, even larger than we can ever think about. Even after so many years, Mankind only tries to understand even one percent of the entire universe and still working. As far as we know and from our research, it is very clear that there are two types of the universe- Known and Unknown Universe.
Known Universe consists of Galaxies, Stars, Planets, Sun, Light, Speed exist which we can see either from devices or from our naked eyes. And the Unknown Universe is beyond these things which we are not able to find.
Scientists said when the Big Bang occurs then there is nothing, just empty space. It means that all the galaxies, stars, planets, light, speed and even time can into the picture after the events of Big Bang. But before all these, there must be some Universe, in which Big Bang happen. And After the events of Big Bang, the Universe started to expand and created Galaxies, speed and time.
Big Bang happens almost millions of years ago according to the human calendar and everything we can see today, light, wind, planets, speed, the raw materials of all these components came from Big Bang and was hidden inside Big Bang for millions of years. Now the speed of light is considered as infinity in space, means there is nothing faster than the light in space and the distance light travels in one year is called ONE LIGHT YEAR. Hence all the things present in the universe never expands faster than the speed of light.
Also using this concept, we can state that our Universe covers more than millions of Light Years and still expanding at a high rate. Even light travels to only million Light Years.
Now the question arises is what is beyond that, where even light can’t reach? All of that is known as the Unknown Universe. No one is ever able to see what is inside the Unknown Universe, because without any source of light, we cannot identify what happens inside the Unknown Universe.
Even using our advanced telescopes and years of research, our Scientist able to identify the planets which are far away from our planet, even we have theories about the mysterious Black Hole but unable to find any single strong source about the Unknown Universe. Events that happen in the Unknown Universe are beyond our Imagination.
Still, the scientists are working hard and working on some theories which might be considered as the truth after some time.