2 ms·> space colonization impractical for close to a century now. How close to a century?by maerF0x0 11y ago> space colonization impractical for close to a century now. How close to a century?rayiner 11y agoGeneral relativity killed the idea of faster than light travel a hundred years ago. Newtonian physics has made leaving earth's gravity on a mass scale for longer than that.maerF0x0 11y agoAwesome. Thanks!