Observable Universe:
Observable Universe is how far we can see in the space from the earth. The universe is expanding and also the observable universe. Really ? How ?? Let us get it more clear. The observable universe expands because of the older and older light coming from the farther and farther stars away. Let us consider this example. To see an object by our eyes, the light from the object first need to reach us. If we switch on a light from a distance of 100 m from the light. The time taken for the light to reach us is 100/300 000 000 = 3.33333333e-7 seconds which is very negligible. But say for example a galaxy at a distance 100 light years away. Then it meant that it took 100 years from the beginning for the light to reach us from that galaxy.
So there are some objects which are very very .... very far, that even the light (speediest object in the universe) has not reached us. So the light from those object has not reached our eyes yet. Those part of universe are not yet observed by us. The current observable universe is around 93 billion light years. More about the topic will be posted soon...Stay tuned
