The white, twisted clouds and the endless shades of blue in the ocean, make the hum of the spacecraft systems, the radio chatter, even your own breathing disappear. There is no wind or cold or snow to tell you that you are connected to Earth.  You have an almost dispassionate - remote, Olympian - and yet so moving that you can hardly believe how emotionally attached you are to those rough patterns shifting steadily below. (Thomas Stafford, American astronaut)
Looking outward to the blackness of space, sprinkled with the glory of a universe of lights, I saw majesty - but no welcome. Below was the welcoming planet. There, contained in the thin, moving, increadibly fragile shell of the biosphere is everything that is dear to you, all the human drama and comedy. That's where life is; that's where all the good stuff is. (Loren Acton, American astronaut)
It seems to me that even the wisest philosophers of the Renaissance or the most daring minds from the past could not estimate the real size of our planet. Earlier, it seemed immeasurably great, almost infinite. Only after the middle of this century did man, having gone up above the Earth into space, see with surprise and disbelief just how small the Earth really is.  Some saw it as an island in the limitless ocean of creation. Some compared it to a spaceship with a crew numbering more than six billion. (Pavel Popovich, Russian astronaut)
 
From "The Home Planet"...