I have only a layman's understanding of Relativity, and I'm somewhat confused about the time dilation concept. The only way that I can think of to ask my question is to present it in an example. A space ship moving at a constant .9 c traveses the distance between two inertial reference frames that are .9 light years apart (about 5.4 trillion miles). An observer at a stationary reference point clocks the event at 1 year. But, due to the dilation effects, the ships clocks shows only .44 years. Assume for this example that reference frames are stationary. Since distance and velocity are constant here, how can can v = ds/dt be valid from the ship's perspective ? Does the ship recognize that it has traveled the 5.4 trillion miles in only .44 light years. I realize that I'm really missing something here.