I have a problem, I've invented a time machine but I'm afraid to use it. If I set my *really does work, definately* time machine to say six months back, I'll be jettisoned into space because Earth is no longer at the point I ported from.
I need to know if there are definate "windows" of time / space I can port to. Say I travel back exactly a year, will I end up 500 meters underground and suffocating because of variations in Earths orbit?
I need to know, I have an important event I need to stop..
TLDR: how accurate is Earth's orbit in the 2D plane?