Mind-boggling considerations from Ethan Seigel:
One of the most counterintuitive lessons of Einstein's relativity is that there's no such thing as absolute space or absolute time. If I ask you when and where you are, you can tell me; but if you and I go to distant locations and I ask you when and where you perceive me to be, what you answer and what I answer won't necessarily match up. As it turns out, there’s no universally good way to define time and space (or distances) for any location other than your own in general relativity. As a result, we have multiple ways of defining these things....
When we use concepts like "time" and "distance" in our everyday language, there are a host of assumptions we rarely think about.
The entire intrguing article can be read here.