Uranus was not quite following its predicted path. Astronomer Urbain Le Verrier concluded that an unseen planet was tugging on it, and calculated where it should be. In September 1846, Johann Galle aimed his telescope at that spot and found Neptune on the very first night, less than a degree from the prediction. A triumph for Newton's laws.
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.