Facts about Titan   Titan, Saturn's largest moon   Titan is the largest moon of Saturn, the second largest in the Solar System (after Ganymede of Jupiter). It was discovered by Christiaan Huygens in 1655.   Titan's rotation period of about 16 days is synchronous to Saturn (meaning the same side always faces Saturn). It is the only moon in the Solar System known to have clouds and a thick, planet-like atmosphere.         Distance from Saturn 1 221 870 km Distance from Sun 1 427 000 000 km (9.54 AU) Diameter (atmosphere) 5550 km Diameter (surface) 5150 km Mass 1/45 that of Earth Average density 1.881 times liquid water Surface temperature 94K (-180 degrees C) Atmospheric pressure at surface 1500 mbar (1.5 times Earth's) Atmospheric composition Nitrogen, methane, traces of ammonia, argon, ethane Orbital period (Titanic day) 15.95 Earth days           Last update: 25 June 2004  •  At Saturn and Titan (http://www.esa.int/SPECIALS/Cassini-Huygens/index.html) More about...  •  More on Saturn's moons (http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=35229 &fbodylongid=1648) Related articles  •  Unusual geology seen during Enceladus fly-by (http://www.esa.int/SPECIALS/Cassini-Huygens/SEMVTX808BE_0.html)  •  Huygens 3D animation of Titan's surface (http://www.esa.int/SPECIALS/Cassini-Huygens/SEMO8G808BE_0.html)  •  Cassini finds atmosphere on Enceladus (http://www.esa.int/SPECIALS/Cassini-Huygens/SEM9RC2IU7E_0.html)  •  Icy surface of Enceladus (http://www.esa.int/SPECIALS/Cassini-Huygens/SEMCVP5TI8E_0.html)  •  Sounds of Enceladus (http://www.esa.int/SPECIALS/Cassini-Huygens/SEM1PO5TI8E_0.html)  •  Hydrocarbon lake on Titan? (http://www.esa.int/SPECIALS/Cassini-Huygens/SEM3SP5DIAE_0.html)  •  Cassini's Hyperion fly-by (http://www.esa.int/SPECIALS/Cassini-Huygens/SEMQUK6DIAE_0.html) Related links  •  NASA JPL Cassini-Huygens site (http://saturn.jpl.nasa.gov/home/index.cfm)  •  Italian Space Agency (ASI) (http://www.asi.it)  •  Space Science Institute (http://ciclops.lpl.arizona.edu/)  •  CIS team (http://cirs.gsfc.nasa.gov/)