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Planets

Characteristics of Saturn

Saturn is the second largest planet in the Solar System. It is one of the two giant gaseous planets within the solar system, with a composition similar to the Sun's. The most prominent feature of Saturn is its ice rings. It also has numerous moons, including the giant moon Titan.

Physical Characteristics of Saturn

In the table below the radius of the planet is defined as the point in the atmosphere where the pressure equals 1 bar (the pressure at sea level on Earth). Two methods are used to derive the rotation of Saturn: the rotation period of Jupiter's magnetic field, and the rotation implied by the flattening of Jupiter at the poles. The observed values in this table are taken from Yoder (1995).[1] Go to table of Saturn's characteristics.

Characteristics of Saturn

GM

3.7931(187±100)×1022 cm3 s−2

Mass

5.683×1029 g

Mean Radius

5.823(2±6)×109 cm

Equatorial Radius

6.026(8±4)×109 cm

Flattening

0.097(96±18)

Surface Gravity

1119 cm s−2

Escape Velocity

3.609×106 cm s−1

Average Density

0.687 g cm−3

Sidereal Rotation Period
(Magnetic)

10h 39m 22.4s

38362.4 s

Sidereal Rotation Period
(Hydrostatic)

10h 36m

38196±72 s

Obliquity to Orbit

26° 44

Sidereal Orbital Period

10746.940 d

Semimajor Axis

9.53707032 AU

Eccentricity

0.05415060

Solar Constant

1.504 × 104 ergs cm−2 s−1

Rings and Moons of Saturn

Saturn stands out for its systems of rings and moons. While other planets have rings, none rival Saturn in the prominence and complexity of its ring structure. The table below lists the rings and moons of Saturn by their distance from Saturn. The rings are listed by their inner radius. All moons inside the inner radius of the E Ring are listed (known before the arrival of the Cassini spacecraft); for moons outside of the E Ring, only those with radii greater than 100 km are given.

The distance column gives the distance of the moons and the inner edges of the disks from the center of Saturn. The Outer Distance columns give the distance of the outer edges of the rings. Both columns are given in units of 108cm and in units of Saturn's equatorial radius. The last two columns give the mass and radius of the moons. The radius is given in kilometers. The distances and sizes in this table are from the Cassini-Huygens Saturn Arrival Press Kit,[2] and the masses are from Norton's 2000.0 Star Atlas and Reference Handbook.[3]

The Rings and Moons of Saturn

Object

Distance

Outer Distance

Mass

Radius

108cm

Rs

108cm

Rs

1022g

km

D Ring

67.0

1.11

74.5

1.24

C Ring

74.5

1.24

92.0

1.53

B Ring

92.0

1.53

117.6

1.95

Cassini Division

117.6

1.95

122.2

2.03

A Ring

122.2

2.03

136.8

2.27

Pan

133.6

2.22

10

Atlas

137.6

2.28

16

Prometheus

139.4

2.31

50

F Ring

140.2

2.33

140.2

2.33

Pandorea

141.7

2.35

42

Epimetheus

151.4

2.51

60

Janus

151.5

2.51

89

G Ring

170.2

2.82

170.6

2.83

E Ring

181.0

3.00

483.0

8.02

Mimas

185.5

3.08

4.5

196

Enceladus

238.0

3.95

7.4

250

Tethys

294.7

4.89

73.8

530

Dione

377.4

6.26

105.2

560

Rhea

527.0

8.75

247.1

764

Titan

1,221.9

20.28

13,530.0

2,575

Hyperion

1,481.1

24.58

1.7

142

Iapetus

3,561.3

59.10

189.4

716

Phoebe

12,952.0

214.94

110

[1] Yoder, Charles F. “Astrometric and Geodetic Properties of Earth and the Solar System.” In Global Earth Physics: A Handbook of Physical Constants edited by T.J. Ahrens, 1–31. AGU Reference Shelf, No. 1. Washington: American Geophysical Union, 1995.

[2] Cassini-Huygens Saturn Arrival: Press Kit. Washington, D.C.: NASA, June 2004.

[3] Norton, Arthur P. Nortons's 2000.0: Star Atlas and Reference Handbook. 18th ed. Edited by Ian Ridpath. Essex, England: Longman Scientific and Technical, 1989.

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