On 14 September 2015, the LIGO detectors recorded gravitational waves, ripples in spacetime that Einstein predicted a century earlier. They came from two black holes merging about 1.3 billion years ago. As the waves passed, they changed the length of the detector's 4-km arms by about a thousandth of a proton's width.
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.