Gene Roddenberry and the Trekkies had it wrong all along. Space is not the final frontier. It never was. The ancients knew that long before there were telescopes with which to ponder space or flying machines with which to pierce it. Space was, and always has been, no more than a continuation of place as we know and occupy it.
But time….ahhh, therein lies our final frontier, the proof of our limitedness, the prison car whose forward thrust we can neither slow nor reverse. Escape it and we are other in a manner and of a substance we can not grasp, so alien are both to our experience and so encapsulated are we in time.