Where From May Aliens Pop In to Earth - A Layman's Perspective

Abstract

A simplistic calculation suggests that travels between galaxies or light-year distant planets are non-realistic considering the unbridgeable gaps for live creatures with relatively short life span. Such discouraging view may seem to imply that we are doomed on earth with almost no hope of colonizing another life-supporting planet at a distant galaxy as long as the journey does not exceed the speed of light.