Beyond about 14 billion light-years, cosmic expansion carries galaxies away from us faster than light. Einstein isn't broken: nothing is racing through space; it's the space between us that's stretching. The dizzying upshot: for the most distant ones, the light they emit today will never reach us.
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.