Suttungr — a small irregular moon of Saturn

Orbit and physical characteristics

Suttungr orbits at an average distance of about 19,667,000 km from Saturn and completes one circuit in roughly 1,029.7 days. Its orbit is markedly inclined and retrograde: the inclination is approximately 174° to the ecliptic (about 151° relative to Saturn's equator), and the eccentricity is near 0.131. These orbital parameters place Suttungr among Saturn's irregular satellites, which are characterized by distant, tilted, and often retrograde orbits.

• Estimated diameter: ~5.6 km
• Semi-major axis: ~19.67 million km
• Orbital period: ~1,029.7 days
• Inclination: ~174° to the ecliptic
• Eccentricity: ~0.131

Origin and group association

Suttungr is usually grouped with the Norse collection of Saturn's moons, a set of irregular, retrograde satellites that share broadly similar orbital distances and directions. One plausible origin scenario is that Suttungr is a fragment produced when a larger irregular satellite—Phoebe or a Phoebe-like body—was disrupted by impacts. The idea that some of the Norse moons originated from collisions or tidal breakups is supported by similarities in orbit and, where available, surface color or albedo measurements.

Discovery, designation and name

The discovery team reported the object in 2000, assigning the provisional label S/2000 S 12. In August 2003 the International Astronomical Union gave the moon the official name Suttungr, drawn from Norse mythology: Suttung (or Suttungr) is a giant associated with the mead of poetry. The IAU's Working Group on Planetary System Nomenclature later adjusted the form of the name to add the Old Norse nominative ending -r, resulting in the current spelling.

Observations and significance

Because of its small size and great distance from Earth, Suttungr is observable only with large ground-based telescopes or sensitive imaging systems. Photometry and follow-up astrometry are used to refine its orbit and to compare surface properties with other irregular moons. Studying satellites like Suttungr helps researchers understand capture processes, collisional evolution in the outer Saturnian system, and the broader population of small bodies in the outer Solar System.

Quick references and further reading

For published orbital parameters and discovery notes consult the discovery circulars and planetary nomenclature resources. Example references include the announcement and orbital data pages maintained by planetary science groups and nomenclature committees. See the orbit summary at orbital data, the eccentricity discussion at eccentricity notes, and hypotheses about collisional origins at collisional studies. The connection to Phoebe has been discussed in multiple reviews (Phoebe link) and the mythological naming background appears in the IAU naming release (naming circular). The poetic legend that inspired the name is summarized in cultural sources (mead of poetry, Suttung story), while the formal IAU decision and grammatical note are recorded by the working group (IAU WG, nominative ending).