The telescope first appeared in the Netherlands: in 1608, spectacle maker Hans Lipperhey applied for a patent on it. Galileo, hearing of the invention, built his own instruments in 1609 and improved them to magnify about twenty times. His decisive contribution was to study the sky methodically and publish his discoveries in 1610, including four moons circling Jupiter.
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.