Here today, gone yesterday.
Recently I’ve been watching a lot of Doctor Who (the 2005-present series). The stories are pretty entertaining but a lot of the “science” tends to be pretty inaccurate or just plain goofy. I’m not faulting the show though (there’s a reason it’s called science-FICTION). There is however, one particular detail that does impress me, and it involves…
In case you aren’t a Doctor Who fan, the TARDIS (Time And Relative Dimension In Space) is the blue police box that the Doctor uses to travel through time (and space)! That’s the key right there, the TARDIS is both a time and space ship.
At first glance that doesn’t seem like such a big deal. The Doctor sometimes travels through time (usually within the UK), and at other times travels through space to different planets. Of course, what doesn’t really ever get brought up, is that when traveling through time, he is also traveling through space.
For instance, assume that right now, you were able to travel through time exactly 24 hours to yesterday. Let’s also assume that you are currently sitting in a somewhat uncomfortable office chair (as I am). If you instantly disappeared today, and reappeared yesterday, in the exact same spot in space, but 24 hours in the past, you would no longer have to worry about sitting in that uncomfortable chair. (w00t!) In fact, you wouldn’t be worrying about anything because you’d be dead. Well, maybe not immediately dead, but certainly after the first 2 or 3 minutes.
The problem is that the Earth is moving (roughly) 67,000 miles per hour so when traveling back in time 24 hours, you would appear in a spot 1,608,000 miles further along Earth’s orbit. This doesn’t even take into consideration Earth’s rotation (about 1,037 mph), the solar system’s orbital speed around the center of the Milky Way galaxy (roughly 420,000 mph) or the speed of the Milky Way galaxy itself, which has been estimated at over 2,000,000 mph! That’s a lot of mileage!
So if you were to only travel through time and yet remain stationary in space, you would reappear far out of reach of Earth (and it’s delicious oxygen). None of this is really mentioned in Doctor Who, but when the Doctor reappears in the same spot, just at a different time, we know that he has also traveled through space. By defining the TARDIS as a space-ship as well as a time-ship the writers have covered their bases. This small detail goes a long way in sating my science-in-sci-fi appetite. This is in stark contrast to something like the phone booth in Bill & Ted’s Excellent Adventure which travels through time by simple using the “Circuits of History”. Then there’s also the Delorean DMC-12 from Back To The Future but at least that’s a moving vehicle.
Got any of your own science gripes or pet peeves from movies or television? Let us know!