Daphnis (moon)

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Daphnis

Daphnis appearing as a small dot that causes ripples on the edges of the Keeler Gap in this image from the Cassini probe
Discovery
Discovered by	Cassini Imaging Science Team
Discovery date	May 6, 2005
Orbital characteristics[1]
Mean orbit radius	136,504.98±0.02 km
Eccentricity	≈ 0
Orbital period	0.5940800 d
Inclination	≈ 0°
Satellite of	Saturn
Physical characteristics
Dimensions	6 − 8 km
Mass	5 − 50 ×1013 kg[2]
Mean density	unknown
Equatorial surface gravity	unknown
Rotation period	synchronous
Axial tilt	unknown
Albedo	≈ 0.5
Temperature	~78 K
Adjectives	Daphnidian

Daphnis (pronounced /ˈdæfnɨs/ DAF-nis, or as Greek Δαφνίς) is an inner satellite of Saturn. It is also known as Saturn XXXV; its provisional designation was S/2005 S 1.^[3][4] Daphnis is about 6 to 8 kilometres in diameter, and orbits the planet in the Keeler Gap within the A ring. It was named in 2006 after Daphnis, a shepherd, pipes player, and pastoral poet in Greek mythology.^[5] He was the son of Hermes, brother of Pan, and descendant of the Titans.

It was discovered by the Cassini Imaging Science Team on May 6, 2005.^[3] The discovery images were taken by the Cassini probe over 16 min on May 1 from a time-lapse sequence of 0.180 second narrow-angle-camera exposures of the outer edge of the A ring. It was subsequently found in 32 low-phase images taken of the F ring on April 13 (spanning 18 min) and again in two high-resolution (3.54 km/pixel) low-phase images taken on May 2, when its 7 km disk was resolved. It had previously been inferred from gravitational ripples observed on the outer edge of the Keeler gap. This moon seems to make waves inside the ring.

The inclination and eccentricity of Daphnis' orbit are very close to zero, and are not distinguishable from zero with present data. Daphnis has an estimated albedo of 50%.

[edit] References

[edit] External links

• CICLOPS imaging: includes a movie of the moon's ripple effect

v • d • e Moons of Saturn Generally listed in increasing distance from Saturn. Temporary names in italics. Ring shepherds moonlets · Pan · Daphnis · Atlas · Prometheus ·  ?S/2004 S 6 · ?S/2004 S 4 · ?S/2004 S 3 · Pandora Co-orbitals Epimetheus · Janus Inner large (and Trojan) Mimas · Methone · Anthe · Pallene · Enceladus · Tethys (Telesto • Calypso) · Dione (Helene • Polydeuces) Outer large Rhea (rings) · Titan · Hyperion · Iapetus Inuit group Kiviuq · Ijiraq · Paaliaq · Siarnaq · Tarqeq Norse group Phoebe · Skathi · S/2007 S 2 · Skoll · S/2004 S 13 · Greip · Hyrrokkin · Mundilfari · Jarnsaxa · S/2006 S 1 · S/2004 S 17 · Narvi · Bergelmir · Aegir · Suttungr · S/2004 S 12 · Bestla · Farbauti · Hati · S/2004 S 7 · Thrymr · S/2007 S 3 · S/2006 S 3 · Surtur · Kari · Fenrir · Ymir · Loge · Fornjot Gallic group Albiorix · Bebhionn · Erriapus · Tarvos Rings of Saturn · Cassini-Huygens · Themis · Chiron