system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: This shower thoughts post; "Somewhere in the galaxy, your childhood is still currently visible. Your past self still exists, traveling through space at the speed of light."
gpt
Light travels at the speed of light. 

If you are 20 years old, the light that reflected off you is 20 light years away from earth now. So in some extremely hypothetical situation, a space traveler 20 light-years away could see that reflection.

Much like how the sunlight you see on earth, took about 8 minutes to reach you from the sun. So you're see the sun as it was 8 minutes ago.