Space Time

A human way of telling the time in years after leaving earth.

What is Space Time?
Humans have used earth years until year 2027 a.k.a Space Time 0 when the world war three started and people started to escape from earth.

YBST
YBST (years before space time) is a human way to tell about the events before Space Time. Example "Humans started mass producing floating cars 9 YBST".

Space Time
Space Time is used the other way around. It is used to tell about the events after the start of Space Time. Example "At Space Time 4 Mars was said to be the new Earth".