The Boötes Void is a vast, nearly empty region roughly 300 million light-years across. Only a few dozen galaxies have been found inside, where thousands would be expected. Voids like this, separated by filaments of galaxies, give the large-scale Universe the look of a giant sponge.
A large share of Earth's water molecules formed in the interstellar cloud that existed before the Sun was even born, more than 4.6 billion years ago. You are literally drinking a cosmic fossil.
By day, the Martian sky looks butterscotch because of fine dust hanging in the air. But at dusk, those same grains scatter blue light forward, creating a bluish glow around the Sun. Rovers have photographed these blue sunsets: the exact reverse of what we see on Earth.