If you are smart enough to create a time machine, my guess is that you would take the orbit of the earth, as well as the orbit of the solar system to project the proper position.
I would not want to be the first one to test that theory.
IF you miscalculated by even a fraction of a second you might end up 1000 feet underground or falling from 10 miles above earth. That is why MY time machine will also be a space ship.