Halley's Comet only swings by the Sun about every 76 years, next in 2061. But Earth passes through the debris it has strewn along its orbit twice a year. The result is two meteor showers: the Eta Aquariids in May and the Orionids in October. You can catch a piece of Halley without waiting until 2061.
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.