Widely acknowledged as one of the most widely distributed photographic images in existence, the "Blue Marble" was photographed by Apollo 17's Harrison Schmitt just a few hours after a trans lunar ...

The "Blue Marble" was the first photograph of the whole ... "We know there are probably billions of stars just in one small section of the Milky Way, maybe even trillions. And we think maybe ...

Is our little blue marble of a planet actually a lot more crowded than we thought? A new study suggests we've been significantly undercounting populations in rural areas, because of the grid-based ...