Space travel is possible (or not) not more than time travel is. Do you thing that you can travel back and forward in space? You may THINK that you can, but you can't. We all travel with earth, and earth travels with sun, and sun travels... etc. The final velocity is too high to reach with any technology, so we can't cancel it or reverse it. It's impossible to go back in space! As it is impossible to go back in time. So: - We ALL travel only forward in space and time. - The small variances in our velocity is more noticeable in space than in time (this is due to the very high speed the light has according to our perception). - Forget about time travelling and think about space travelling first! Any comment?