

"Our planet is our spaceship," said NASA astronaut Sandra Magnus, who recently returned to Earth after spending about 4 1/2 months in space. "It looks very fragile from here, and it's very easy to take it for granted when we're living on it, when it seems so big and so massive. But it's not. It's very small and very fragile."


"When you look out the window, you notice how incredibly thin our atmosphere is, how such a fragile shell of air we have that surrounds our planet and makes it habitable," she said before leaving the station. "And you can read that in a book, but until you see it it doesn't strike home."

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This island Earth



"The amazing public perception of that stunning photo gave everybody an awareness that the Earth was an oasis out there in a very barren, harsh cosmos," said former astronaut Thomas Jones, a planetary scientist and co-author of the book "Planetology." "I think those images became the icon of the environmental movement in its earliest phase."


"That's what the space program gives us is the ability for everybody to share in the astronauts' vantage point," Jones, a four-time spaceflyer, told


A station with a view



"There's no doubt, when you look down at the Earth from here, you're just overwhelmed by how beautiful it is," Barratt said this week, adding that two things immediately jump out. "One is how much you miss it, and two, is how much you really want to take care of it as best you can."


"It makes you think about our planet as a whole system," Magnus said. "We're all there together living together as human beings and other organisms and we have to take care of each other."
