Which way is ‘down’ has a different answer depending on where you are on Earth, in the solar system, in our galaxy and beyond ...

Oh, we humans do love a cleanly defined boundary, don’t we? They make things easier, after all. If we’re trying to categorize something, knowing what labeled bin to put it in is handy. If we’re ...

And the earth was without form and void, and darkness was upon the face of the deep. Sometimes, if the night is dark and clear enough, you can look up and see the Milky Way in its arc across the sky.

Test your knowledge on our solar system, from the biggest and smallest planets to the behemoth mountain on Mars. When you purchase through links on our site, we may earn an affiliate commission.

Earth is the only life-supporting planet in our Solar System. Until now. Today, we’re bringing Kepler 22-b into our planetary ...