Facts about Saturn


Views on approach to Saturn
 
Saturn from 56 million kilometres
 
Saturn is the sixth planet from the Sun and is the second largest in our Solar System. Much of what is known about the planet is due to the US Voyager explorations in 1980-81.
 
  
Orbit1 429 400 000 km (9.6 AU) mean distance from Sun
Diameter (equatorial)120 536 km
Diameter (polar)108 728 km
Orbital period (Saturnian year)29.46 Earth years
Saturnian day10 hours 39 mins
Core temperatureApprox. 12 000K (11 700°C)
Cloud-top temperature150K (-139 °C)
Average density0.7 g per cubic cm (0.7 times that of water
Atmospheric composition96% hydrogen and 4% helium with traces of water, methane and ammonia
Moons34
  
 
Saturn is visibly flattened at the poles, a result of the very fast rotation of the planet on its axis.

It is different from Earth in that there is no sharp distinction between atmosphere and the planet surface. Instead there is a slow gradual change from gaseous atmosphere to liquid. The pressure increases with depth, and the hydrogen and helium gases become liquid.

Thus, Saturn does not have a 'surface' in the same sense that the Earth does. It would be impossible to land a spacecraft, though one could be made to drop slowly with a parachute and transmit information until the intense pressure of Saturn's atmosphere crushed it.
 
 
  
Last update: 11 May 2005

 •  At Saturn and Titan (http://www.esa.int/SPECIALS/Cassini-Huygens/index.html)

More about...

 •  More on Saturn (http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=35131)

Related articles

 •  Cassini-Huygens factsheet (http://www.esa.int/SPECIALS/Cassini-Huygens/SEMLIRR1VED_0.html)
 •  Christiaan Huygens: Discoverer of Titan (http://www.esa.int/esaSC/SEMJRT57ESD_index_0.html)
 •  Jean-Dominique Cassini: Astrology to astronomy (http://www.esa.int/esaSC/SEMJ2T57ESD_index_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)