When I was a kid I thought that spacetime was created by mass. I thought that if you were to ever find the end of the universe you wouldn't be able to travel beyond because you would just create new spacetime everywhere you went.

And I thought that was scientific consensus. No idea where I got it from, though.

Maybe this is why Stephen Hawkings time travellor party never worked out lol

I should hope that if we had time travel landing pads, we'd have a pretty good log of maintenance times in the future.

The tough part to figure out, though, is that the more a pad is used, the more maintenance it requires, which in turn modifies the logs.

A time machine, at its very very core, is a literary device. You wouldn't bring up this nuance unless it was important to the plot of the story.

It's like warp drives. The point of warp or any FTL travel is to skip the boring parts. You only learn about warp drives when something goes wrong.

This. I like that Dr who actually has had this problem in universe. I don't recall the episode, but he went to earth and ended up at the right time, but not the right place, since you know, earth is moving.

Even if you were to use the sun as a reference we orbit the sun (relative to the position of the sun) at some incredible speeds. Time of day factors in, since we're rotating rather fast as well. So getting the right coordinates in space for a particular day, and a particular time in a particular year, for a specific place.... Well, good luck.

Which isn't to mention the fact that we're in a galaxy, which is moving as well, so using a point of reference outside the solar system becomes insane to try and calculate; which is what you would have to do in order to enable travel outside of our solar system with something like a TARDIS.