In 1974, Stephen Hawking showed that quantum effects make black holes emit a faint glow, so they slowly lose mass. But it's staggeringly slow: a black hole with the Sun's mass would take about 10⁶⁷ years to vanish, a 1 followed by 67 zeros. This Hawking radiation has never been observed directly.
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.