Neptune is farther from the Sun, but Uranus holds the cold record, with about −224 °C measured in its atmosphere. The reason is still partly a mystery. Unlike the other giant planets, Uranus gives off very little internal heat, as if its core had lost much of its energy reserve, possibly after a giant collision.
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.