about saturn

SATURN   saturn in natural color approaching equinox, photographed by Cassini in July 2008. The little white dot in the bottom left corner is Titan.
Designations
Pronunciation	/ˈsætərn/
Named after	Saturn
Adjectives	Saturnian, Cronian
Orbital characteristics[2]
Epoch J2000.0
Aphelion	10.086 AU (1.509 billion km)
Perihelion	9.024 AU (1.350 billion km)
Semi-major axis	9.5549 AU (1.429 billion km)[2]
Eccentricity	0.05555
Orbital period	29.4571 yr 10,759.22 d 24,491.07 Saturnian solar days[3]
Synodic period	378.09 days[4]
Average orbital speed	9.69 km/s (6.02 mi/s)[4]
Mean anomaly	317.020°
Inclination	2.485240° to ecliptic 5.51° to Sun's equator 0.93° to invariable plane[5]
Longitude of ascending node	113.665°
Argument of perihelion	339.392°
Known satellites	62 with formal designations; innumerable additional moonlets.[4]
Physical characteristics
Mean radius	58,232 ± 6 km (36,184 ± 4 mi)[6][a]
Equatorial radius	60,268 ± 4 km (37,449 ± 2 mi)[6][a] 9.4492 Earths
Polar radius	54,364 ± 10 km (33,780 ± 6 mi)[6][a] 8.5521 Earths
Flattening	0.09796±0.00018
Surface area	4.27×1010 km2 (1.65×1010 sq mi)[7][a] 83.703 Earths
Volume	8.2713×1014 km3 (1.9844×1014 cu mi)[4][a] 763.59 Earths
Mass	5.6836×1026 kg (1.2530×1027 lb)[4] 95.159 Earths
Mean density	0.687 g/cm3 (0.0248 lb/cu in)[4][b] (less than water)
Surface gravity	10.44 m/s2 (34.3 ft/s2)[4][a] 1.065 g
Moment of inertia factor	0.210[8] (estimate)
Escape velocity	35.5 km/s (22.1 mi/s)[4][a]
Sidereal rotation period	10.55 hours[9] (10 hr 33 min)
Equatorial rotation velocity	9.87 km/s (6.13 mi/s; 35,500 km/h)[a]
Axial tilt	26.73°[4] (to orbit)
North pole right ascension	2h 42m 21s; 40.589°[6]
North pole declination	83.537°[6]
Albedo	0.342 (Bond) 0.499 (geometric)[4]
Surface temp. min mean max 1 bar 134 K (−139 °C)[4] 0.1 bar 84 K (−189 °C)[4]
Apparent magnitude	+1.47 to −0.24[10]
Angular diameter	14.5″ to 20.1″[4] (excludes rings)
Atmosphere[4]
Scale height	59.5 km (37.0 mi)
Composition by volume	by volume: ≈ 96% hydrogen (H 2) ≈ 3% helium (He) ≈ 0.4% methane (CH 4) ≈ 0.01% ammonia (NH 3) ≈ 0.01% hydrogen deuteride (HD) 0.0007% ethane (C 2H 6) Ices: ammonia (NH 3) water (H 2O) ammonium hydrosulfide (NH 4SH)