ATTENTION SCIENCE NERDS

[The Man]

And we told you we're close. So now let's talk about other sciency things we were promised that haven't happened yet. I mean, I was promised time travel in 1985. I'm waiting for my time travel.

along with time travel.

The TARDIS is actually the only practical time machine ever conceived.

What an obscenely presumptuous statement. That's like saying "long-sleeved shirts are the only practical clothing ever conceived."

Not really. Any time machine that isn't also a space ship or can guarantee it lands on Earth in another time period will kill its occupants. Very few time machines actually have this ability, but with the TARDIS it's built into the name. And since it predates most other space travelling time machines it gets the credit for being the first.

You're neglecting that gravity bends spacetime. Any old time machine can and will be affected by gravitational forces past, present and future, ie dumping the vessel back in the same geographical locale it left from. More or less. Continental drift could pose a problem.

It's highly unlikely that all of this would be enough to counteract the revolution of the earth around the sun, and even if there weren't that the rotation of the earth about its axis could cause problems too (since some parts of the earth are higher up than others and you could easily end up teleporting yourself into solid ground or several miles above the surface of the earth).