Two-Faced Planet That Looks Like Nothing Else in the Universe

The space around us is huge and full of mysteries. Space isn't supposed to be black: there are stars everywhere. But you don't see stars wherever you look because some of them haven't existed long enough for their light to reach Earth! Saturn is less dense than water, so if it were thrown into a giant pool, it would float. Mercury and Venus are the only planets in the Solar System that have no known moons.