Did you know that the night sky is an illusion? Stars are so far away that it takes millions or billions of years for the light to shine on the Earth. This means that when we see the stars, the 'stars' we are seeing aren't actually there anymore. They have moved but since the light took so long to get to Earth, the stars aren't there. Scientists think that if we put a giant mirror 20 thousand light-years from earth and looked into it, we would be able to see the dinosaurs. This proves that time travel is possible and we just don't have the technology yet.