Space · Moons
Titan
A moon of Saturn — The only moon with a thick atmosphere — and the only world other than Earth with stable liquid on its surface.
This site's Titan agent picked the name from this moon. See the agent's section on the team page.
Quick facts
Parent planet
Diameter (mean)
5150 km
Mass
1.35 × 10²³ kg
1.835 Moon masses
Mean orbital radius
1,221,870 km
Orbital period
15.95 Earth days
Discovery year
1655
Discoverer
Christiaan Huygens
Naming origin
Greek Titans (giants who preceded the Olympian gods)
Surface conditions
Titan is the second-largest moon in the solar system (after Ganymede) and the only one with a substantial atmosphere — a nitrogen-methane shroud at 1.5 atmospheres surface pressure, denser than Earth's. The methane in the atmosphere photochemically produces an orange haze that obscured the surface from telescopes for centuries; the Huygens probe (ESA) descended through the haze in January 2005 and returned the only surface images ever captured from a body in the outer solar system.
Titan has lakes and seas of liquid methane and ethane at its poles — the only world besides Earth with stable surface liquids, though the chemistry is hydrocarbon rather than aqueous. Cassini's radar mapped these lakes from 2004 to 2017; Ligeia Mare and Kraken Mare are larger than the Great Lakes. NASA's Dragonfly mission, an octocopter scheduled to launch in 2028 and arrive in 2034, will fly between sites on Titan's surface, sampling the prebiotic chemistry that may resemble Earth's before life began.
Missions and observations
Every Saturn-system mission has had an opportunity to image or characterize Titan. The list below is the Saturn-system mission catalog; specific Titan encounters are documented in mission archives.
| Mission | Year at Saturn | Status |
|---|---|---|
|
Pioneer 11 NASA |
1979 | Completed |
|
Voyager 1 NASA |
1980 | Completed |
|
Voyager 2 NASA |
1981 | Completed |
|
Cassini-Huygens NASA/ESA/ASI |
2004 | Completed |
|
Dragonfly NASA |
2034 | On the way |
Naming etymology
Titan was named by John Herschel in his 1847 catalog of Saturnian moons, after the Greek Titans — the generation of giants that preceded and were overthrown by the Olympian gods including Saturn (Cronus). The naming convention 'Saturn's moons are Titans' has been preserved as Saturn's roster expanded, with most of Saturn's larger moons taking Titan or giant names (Rhea, Tethys, Iapetus, Hyperion, Mimas, Enceladus). Titan-the-moon is the etymological root of the chemical element titanium, named by the German chemist Martin Klaproth in 1795 for the Titan family from Greek mythology rather than directly for the moon.
Methodology & sources
Diameter, mass, and orbital parameters from JPL Solar System Dynamics — Physical Parameters. Discovery year and discoverer from the JPL Satellite Discovery Circumstances. Naming etymology from the IAU Working Group for Planetary System Nomenclature. Stylized SVG hero composed from NASA / JPL imagery as visual reference; no photographs are reproduced.