Saturn's Moons

List of Moons

Saturn currently has 61 known moons, six of which have been discovered in data gathered by Cassini. Two more possible discoveries by Cassini still await final confirmation, as the objects might not be proper moons but instead are transient in nature. When Cassini-Huygens was launched in 1997 there were only 18 known Saturnian moons. In addition to the Cassini discoveries, reanalysis of data from the Voyager 2 spacecraft, as well as Hubble observations and ground-based observations of Saturn have led to the further discoveries.

Discoveries by Cassini

3 March 2009 - S/2008 S1
Discovered in two images taken on 15 Augustus 2008 by Cassini's narrow-angle camera, the Cassini Imaging Science Team has found a moonlet embedded within a ring arc in Saturn's G ring. Designated as S/2008 S1, the moonlet is too small to be resolved by Cassini’s cameras, so its size cannot be measured directly. However, its size is preliminary estimated by comparing its brightness to another small Saturnian moon, Pallene, and found to be ~250 m. Since its discovery the object has been confirmed and identified 21 times in images taken between 15 June 2007 and 20 February 2009. It orbits Saturn at a distance of 167 500 km.
Naming update: the moon has been named Aegaeon.

19 July 2007 - S/2007 S4
Following first detection in images obtained by Cassini's wide-angle camera on 30 May 2007, Saturn's 60th moon was confirmed by analysing more Cassini-Huygens images. The moon, designated S/2007 S4 and yet to be given an official name, is thought to be ~2 km wide and its orbit lies between those of Methone and Pallene.
Naming update: the moon has been named Anthe.

10 May 2005 - S/2005 S1
A small new moon has been found orbiting within the Keeler gap in Saturn's A ring at 136 500 from the planet's centre. The object is temporarily designated S/2005 S1 and was found to be roughly 7 km across. The moon's gravitation influences the edges of the Keeler gap where the ring material is seen to form wavy patterns. S/2005 S1 was first seen in images taken on 1 May 2005.
Naming update: the moon has been named Daphnis.

24 February 2005 - S/2004 S5
A tiny moon, about 5 km across, was discovered in images taken on 21 October 2004 and has been designated S/2004 S5. It is a companion, or Trojan moon of Dione and trails Dione in its orbit around Saturn. Dione has another known Trojan moon, Helene that orbits 60 degrees ahead of Dione.
Naming update: the moon has been named Polydeuces.

9 September 2004 - S/2004 S3 and S/2004 S4
Two small objects, temporarily designated S/2004 S3 and S/2004 S4, have been seen orbiting near Saturn's outer F ring. The tiny objects orbit the planet at a distance of approximately 141 000 km from Saturn's centre. Their nature, moon or temporary clump, is yet to be confirmed. They were found in images taken on 21 June 2004.

16 August 2004 - S/2004 S1 and S/2004 S2
Two new moons have been discovered orbiting between Mimas and Enceladus. The moons are approximately 3 km and 4 km across. Provisionally named S/2004 S1 and S/2004 S2, they are located respectively 194 000 km and 211 000 km from the planet's centre. One of them, S/2004 S1, may be an object spotted in a single image taken by NASA's Voyager spacecraft 23 years ago, called at that time S/1981 S14.
Naming update: the moons have been named Methone and Pallene respectively.

Saturn's Moons

	No.	Distance  (km)	Mass (1020 kg)	Radius  (km)	Mean ρ (kgm-3)
Pan	XVIII	133 583	0.00003	10	630
Daphnis	XXXV	136 500	-	~7	-
Atlas	XV	137 670	0.0001	18.5×17.2×13.5	630
Prometheus	XVI	139 353	0.0033	74×50×34	630
Pandora	XVII	141 700	0.0020	55×44×31	630
Epimetheus	XI	151 422	0.0054	69×55×55	600
Janus	X	151 472	0.0192	97×95×77	650
Aegaeon	LIII	167 500	-	~0.25	-
Mimas	I	185 520	0.375	209×196×191	1140
Methone	XXXII	194 000	-	~3	-
Anthe	XLIX	197 700	-	~2	-
Pallene	XXXIII	211 000	-	~4	-
Enceladus	II	238 020	0.65	256×247×245	1000
Tethys	III	294 660	6.27	536×528×526	1000
Telesto	XIII	294 660	0.00007	15×12.5×7.5	1000
Calypso	XIV	294 660	0.00004	15×8×8	1000
Dione	IV	377 400	11.0	560	1470
Helene	XII	377 400	0.0003	18×16×15	1500
Polydeuces	XXXIV	377 400	-	~4	-
Rhea	V	527 040	23.1	764	1240
Titan	VI	1 221 830	1345.5	2575	1881
Hyperion	VII	1 481 100	0.2	185×140×113	1500
Iapetus	VIII	3 561 300	15.9	718	1020
Kiviuq	XXIV	11 370 000	-	~7	-
Ijiraq	XXII	11 440 000	-	~5	-
Phoebe	IX	12 952 000	0.072	115×110×105	1300
Paaliaq	XX	15 200 000	-	~10	-
Skathi	XXVII	15 650 000	-	~3	-
Albiorix	XXVI	16 390 000	-	~13	-
S/2007 S2		16 560 000	-	~6	-
Bebhionn	XXXVII	17 119 000	-	~6	-
Erriapus	XXVIII	16 950 000	-	~4	-
Siarnaq	XXIX	17 530 000	-	~16	-
Skoll	XLVII	17 665 000	-	~6	-
Tarqeq	LII	17 920 000	-	~7	-
Tarvos	XXI	17 983 000	-	~15	-
Greip	LI	18 105 000	-	~6	-
Hyrrokkin	XLIV	18 437 000	-	~8	-
S/2004 S13		18 450 000	-	~6	-
S/2004 S17		18 600 000	-	~4	-
Jarnsaxa	L	18 600 000	-	~6	-
Mundilfari	XXV	18 710 000	-	~3	-
S/2006 S1		18 981 135	-	~6	-
Narvi	XXXI	18 720 000	-	~3	-
Bergelmir	XXXVIII	18 750 000	-	~6	-
Suttungr	XXIII	19 459 000	-	~7	-
S/2004 S12		19 650 000	-	~5	-
S/2004 S07		19 800 000	-	~6	-
Hati	XLIII	19 856 000	-	~6	-
Bestla	XXXIX	20 129 000	-	~7	-
Farbauti	XL	20 390 000	-	~5	-
Thrymr	XXX	20 474 000	-	~7	-
S/2007 S3		20 518 500	-	~5	-
Aegir	XXXVI	20 735 000	-	~6	-
S/2006 S3		21 132 000	-	~6	-
Kari	XLV	22 118 000	-	~7	-
Fenrir	XLI	22 453 000	-	~4	-
Surtur	XLVIII	22 707 000	-	~6	-
Ymir	XIX	23 040 000	-	~18	-
Loge	XLVI	23 065 000	-	~6	-
Fornjot	XLII	25 108 000	-	~6	-

Notes:

• Distance is mean distance from the centre of Saturn in km
• Mass is in units of 10²⁰ kg
• Radius is in units of km
• Mean density ρ is in units of kgm^-3
• "No." lists the number in Roman numerals assigned to the moons that have been named: 53 (LIII) out of the 61 moons, as of June 2009. Eight moons are yet to be named and until then only have temporary designations of the form S/YYYY S# (first column)

Pan

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Last Update: 05 Jun 2009