Christiaan Huygens (1629–1695), Dutch mathematician, physicist and astronomer, son of Constantijn Huygens

Cassini–Huygens, mission to Saturn and Titan

Huygens probe is the portion of the Cassini-Huygens mission which landed on Saturn's moon Titan on January 14, 2005

Constantijn Huygens (1596–1687), Dutch poet and composer, father of Christiaan Huygens

Huygens' principle

Jan Huyghen van Linschoten, (1563–1611), Dutch voyager and historian

2801 Huygens, an asteroid named after the astronomer

Huygens Software, a microscope image processing package

Huygens, one of Mars' crater

Mons Huygens, the mountain of Earth's Moon