When you look into a night sky you see the stars far away, you're seeing them because of the light which travels from them to you. Now it takes time for light to travel here, so what you are doing is seeing the stars as they were in the past, the amount of time it has taken for the light to reach us and the further and further away those stars are, the further back in time you are looking. Now you are seeing a star that is say six thousand years ago, imagine somebody on that star looking at us, they would be seeing us as we were six thousand years ago. Which of those two is now? So space and time are linked together. As we are looking across space, we are looking back in time. -Prof. Frank Close