Does time dilation only affect matter that has mass? For example, A spaceship is 1 light year away from Earth at rest. It sent out a radio wave to Earth then travels at 99.99% of the speed of light. On Earth, from our perspective, we will receive that radio wave 1 year later but the spaceship arrives 70 years later. If that spaceship speed up to 99.999999% of the speed of light, it will take 7000 years from our perspective to see that spaceship. As a result, from our perspective, the faster that ship travels, the later it arrives, how does that makes sense?