Add relativity into the mix, and the properties of energy and light become downright mysterious.
This GIF by James O'Donoghue using NASA imagery, although showing the speed that light travels, really highlights the vast cosmic distances that exist beyond our human & planetary scales.
This visualization illustrates the difficulty that the human race is going to have with space travel by "conventional" means - by which I mean trying to accelerate through physical space to a percentage of light speed to reach other star systems.
I think the answer is the development of technology that has been imagined in Star Trek and described by Bob Lazar, who claim to have worked on reverse-engineering spacecraft at the S-4 facility near the once-secret, now-infamous Area 51 test site.
We need to create technology that is able to manipulate gravity in such a way that it can warp space-time, so that the traveler is warped to the destination faster than light would be able to travel through the same space. I think the ideas of Nassim Haramein are leading us in the direction of technology.
Whether it's eventually feasible remains to be seen, but it seems to be the only way to travel through interstellar space without taking generations of humans, or centuries of sending out AI-driven machines.
Perhaps another option is to become beings of pure light ourselves, so that relativistically time stops altogether. However, then our need to explore and physically experience things would be irrelevant anyway...