To mark the end of Earth Week, here are some instructive photos that should put everything into perspective:
Here is Earth, the whole world, everything that we know and ever knew, right here in one picture
Here is our Earth and its moon viewed from Mars. That little blue bubble in all that darkness is all we have.
Within this thin veil of blue gas on the surface of a round rock are all of our lives. Beyond it is the hostile nullity of space. Beyond is nothing but exposure to radiation, the burning heat of the sun, and the freezing dark in which no life is possible; the airless soundless void which is bigger than we can possibly imagine.