As a child or adult, one question that have definitely aroused in everyone's mind is "Is this universe infinite or it has some boundaries?" as a science or astronomy student this might be the first question to arouse in students mind. Coming back to the answer of this beautiful question- The observable universe is still huge but it has limits. This is because we know that the universe isn't infinitely old - we know that the big bang occured some 13.8 billion years ago. So from this we can conclude that the light has had only 13.8 billion years to travel and hence defines the limitations of universe. All we know or scientists believe is that universe is still far above from our observable distance but at some point it has limits for sure.
We all know that water is abundant in space and is made up of hydrogen created in the Big Bang and oxygen released from dying stars. According to studies planets of our solar system were created around 4.60 billion years ago from clumps of rocks spinning around the Sun. Earth was moulded from rocks that came from the inner solar system where the fierce heat of the sun would have boiled away the water. So, the water would have come later. But according to many geochemical studies or theories have concluded that asteroids are most likely the primary source of Earth's water. Carbonaceous chondrites –which are a subclass of the oldest meteorites in the Solar System–have isotopic levels most similar to ocean water.