I've been reading "The Order of Time" by Carlo Rovelli and have been really interested in the concept of time. From a scientific perspective, time is quite interesting. It always seems to move forward at this constant pace, yet according to the laws of physics, we see that time is not a constant thing. The faster we move, the slower time ticks.
While it is almost immeasurable at everyday speeds, it has been shown to be true. Take two identical, high precision watches and fly one on a plane and keep the other on the ground then bring them back together.
The one that took the flight will be ever so slightly behind the other. If we could travel faster towards lightspeed, the difference would be immense. That isn't just the clock ticking slower, but true for whatever was moving that fast. Just imagine taking a flight to a distant star and back only to realize that decades past by on Earth. Not only that, but just take a moment to ponder the thought of what is happening this very second here on Earth, on Mars, on Jupiter, and out towards one of the stars in the sky. Unbelievably, there is no such thing. When we think of relatively short distances, Sure, we can get the feeling that there is the same moment happening here as is, say, Japan. But the farther you go, the weirder this concept becomes.
Even the light we see from the sun takes around 7 minutes to reach us, so what we see as the sun is not how it currently looks. Imagine a sphere around you with a radius of 100 light-years. If there were a sentient being looking at the Earth from that distance, you would not have appeared to have been conceived, the internet had yet to be invented, and the first burial at the UK's tomb of the unknown soldier would just about have taken place. This is because 100 light-years out, it would appear to be 1921 on Earth. And suppose we target our telescope at that sentient being 100 light-years away, we would only spot them if they were there 100 years in the past (to us). I really recommend this book should you have the time to read it.