The Science of Back to the Future

How far did the Earth move?
How far did the Earth move?

Here’s a pretty cool assessment of the science of Back to the Future:


“Watthew Mrather” writes: The DeLorean can’t go anywhere in space, except in the conventional driving/flying sense.  Your [sic] always in the same place you left, but in a different time.


Well, for starters, that’s not a question, “Mr. Mrather,” but I’ll go along with it anyway.  Remember, though: without proper punctuation and grammar, we are no better than the animals.

In fact, in order to pull off the kind of time travel we see in the Back To The Future trilogy–the kind where the traveler is transposed in time, but remains stationary in the same relative position to where he/she left–the DeLorean would have to be an outstanding space ship, in addition to its already laudable work as a time-ship.  A major issue of freely traveling within time while limiting one’s self to a local reference frame–say, a California mall parking lot–is that the reference frame itself isn’t stationary.  As an illustration, let’s figure out how far the DeLorean would have to travel in order to stay in sync with the Earth over a relatively small time-jump.  We’ll look at the simplest example (and the first one, diagetically speaking) of the whole BTTF trilogy.  You all remember the scene, right?  (Spoiler alert: Professor Plum and Alex P. Keaton send a dog one minute into the future.)