Hi. I'm learning about special relativity and want to see whether I understand it correctly. As such, I had 2 thought experiments that I answered, and I want to see whether these answers are correct. If not, could someone please tell me the correct answers? Thanks! Thought Experiment 1: Super long straight-away with a start line and a big digital clock at the start line. Person1 (who had a running start) travels at a constant speed of half the speed of light and leaves the start line at "0" seconds. When the start clock hits 1 second (based on an observer standing at the start clock). a light beam (a photon) is fired straight ahead from the start line. How long does it take the light beam to reach Person 1? From Person1's vantage point, he left when the start line said 0. He got 93,000 miles away and by that time his watch showed 1 second, but looking back at the clock at the start line, it appeared to show 0.5 seconds to him (from an "outside omniscient observer," this is objectively when the light beam left, and the start line actually showed 1 second). The light beam caught Person1 when his watch showed 2 seconds, but the start clock showed 1 second from his vantage point if he were to be looking back. So I guess when we say "light approaches all constant-speed observers at 186,000 meters/second," in this case, we're saying that based on the time the observer sees on the clock from the start vs. end time. And the light did not "age" at all because it showed 1 second on the clock when it left and when it arrived from its vantage point. From the vantage of a Person2 standing next to the start clock, I think the clock showed 3 seconds when it appeared the light beam caught Person1, which is 2 seconds after the light beam left. Thought experiment 2: Let's say the universe is super big with, oddly enough, no movement of any celestial bodies, and you live on Planet 1 (far west part of the universe). You get shot at 99.9999% the speed of light toward Planet 2 (far east -- trillions of light years away). Ignore the fact that you would have a ridiculously large amount of mass and not actually live a normal life, and just assume you age like a normal person (someone who dies after ~80 years). Assume Planet 3 is 80 light years east of Planet 1. Do you die before you reach Planet 2? My answer is yes, you die around the time that you pass Planet 3.