Titan may refer to two widely known uses in science and mythology. Titan is the largest moon of Saturn and the second-largest moon in the solar system. It was discovered by Christiaan Huygens in 1655. Titan orbits Saturn at about 1.2 million kilometers and has a sidereal orbital period of roughly 15.9 days; it is tidally locked to Saturn. The moon has a thick atmosphere, composed mainly of nitrogen with a significant fraction of methane, producing a surface pressure near 1.5 bars. Its surface temperature remains around -179 degrees Celsius. Features include extensive dune fields, methane-ethylene lakes and seas near the polar regions, and evidence suggesting a subsurface ocean and possible cryovolcanic activity. Titan is a focus of planetary science missions, with NASA’s Dragonfly rotorcraft lander planned to study its chemistry and habitability capitalizing on its complex organic environment. In Greek mythology, Titan refers to a member of the ancient race of giants who ruled before the Olympian gods. The Titans were the offspring of Gaia (Earth) and Uranus (Sky) and included figures such as Cronus, Rhea, Oceanus, Tethys, Hyperion, Iapetus, Themis, and Mnemosyne. They governed cosmic and natural forces prior to their defeat by the Olympian pantheon in the Titanomachy. Some Titans, like Prometheus and Atlas, have enduring roles in myth and literature. The term titan also enters contemporary usage as a metaphor for something of great size or power.