My Question is very interesting. I want an exact answer after correct assessments. Let there is a box or rocket or something in which light starts from point A to point B. When Light is generated from point A, at the exact point that thing box or rocket or frame moves from point X and it moves until Light reaches from A to B, now as it reaches B, that thing box or rocket stops and it covers the distance from point X to point Y and stops at that point. Now Distance D1 be the distance light covers from A to B, which can be found using formula (d = ct) and let D2 be the distance between point X and point Y. We can find D2 using (v * t') v is the speed of rocket or box, while t' is the relative time. If there is another way ot find it then kindly state it. My question is that can D2 be equal or greater than D1? and we know v has a limit that it should be less than c. Which distance will be greater? D1 or D2?