Apollo astronauts left seismometers on the Moon that ran until 1977. In 1969, the ascent stage of Apollo 12's lunar module was deliberately crashed into the surface, and the Moon kept vibrating for nearly an hour. With no water to dampen the waves, lunar rock rings far longer than rock on Earth.
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.