At the beginning of “An Inconvenient Truth” Al Gore shows the audience two iconic Apollo images, Earthrise and Blue Marble. I remember seeing those pictures as a teenager and feeling the shock of scale. There we all were, every last one of us. Human beings living on a fragile blue globe suspended in the middle of nowhere. And all of history has happened on that tiny rock.
As an aside, the link to Earthrise above has some interesting history of the image.