Christiaan Huygens, son of the Dutch poet and composer Constantijn Huygens, was born in the Hague on April 14, 1629. I tend to say “hoygns”, but he was Dutch, which I don’t speak, so other pronunciations are probably available.
Huygens had all sorts of good ideas, mainly about maths and physics (waves, optics, probability), but also got interested in extraterrestrial life about 400 years before it became fashionable. From our perspective though, he was rather interested in astronomy. With a home-made telescope a good deal more powerful than Galileo’s, the construction of which was aided by his brother, Constantijn Jr., he was able to spot for the first time (in 1655) that the rings of Saturn were a flattened, inclined disc, separated from the planet. Galileo had spotted the rings previously, but wasn’t able to make out what they were, and was tempted towards the opinion that the planet might be in three parts.
Huygens also discovered Saturn’s largest moon, Titan, on march 25th 1655. He called it Luna Saturni (Saturn’s moon) because at the time it was the only one known.
Not content with being an astronomical genius, among his other triumphs were the invention of the pendulum clock, and the wave theory of light.