Aegir, also Saturn XXXVI (provisional designation S/2004 S 10), is a

natural satellite A natural satellite is, in the most common usage, an astronomical body that orbits a planet, dwarf planet, or small Solar System body (or sometimes another natural satellite). Natural satellites are often colloquially referred to as ''moons'' ...

Saturn Saturn is the sixth planet from the Sun and the second-largest in the Solar System, after Jupiter. It is a gas giant with an average radius of about nine and a half times that of Earth. It has only one-eighth the average density of Earth; h ...

. Its discovery was announced by

Scott S. Sheppard Scott Sander Sheppard (born 1977) is an American astronomer and a discoverer of numerous moons, comets and minor planets in the outer Solar System. He is an astronomer in the Department of Terrestrial Magnetism at the Carnegie Institution for Scie ...

David C. Jewitt David Clifford Jewitt (born 1958) is a British-American astronomer who studies the Solar System, especially its minor bodies. He is based at the University of California, Los Angeles, where he is a Member of the Institute for Geophysics and Pl ...

Jan Kleyna Jan T. Kleyna is a postdoctoral astronomy researcher at the University of Hawai'i Institute for Astronomy. His area of interest is galaxy dynamics, and he has worked to develop codes for the real-time detection of moving objects such as Jovian ...

, and

Brian G. Marsden Brian Geoffrey Marsden (5 August 1937 – 18 November 2010) was a British astronomer and the longtime director of the Minor Planet Center (MPC) at the Center for Astrophysics Harvard & Smithsonian (director emeritus from 2006 to 2010). ...

on May 4, 2005, from observations taken between December 12, 2004, and March 11, 2005. Aegir is about 6 kilometres in diameter, and orbits Saturn at an average distance of 19,618 Mm in 1025.908 days, at an

inclination Orbital inclination measures the tilt of an object's orbit around a celestial body. It is expressed as the angle between a Plane of reference, reference plane and the orbital plane or Axis of rotation, axis of direction of the orbiting object ...

of 167° to the

ecliptic The ecliptic or ecliptic plane is the orbital plane of the Earth around the Sun. From the perspective of an observer on Earth, the Sun's movement around the celestial sphere over the course of a year traces out a path along the ecliptic again ...

(140° to Saturn's equator), in a retrograde direction and with an

eccentricity Eccentricity or eccentric may refer to: * Eccentricity (behavior), odd behavior on the part of a person, as opposed to being "normal" Mathematics, science and technology Mathematics * Off-center, in geometry * Eccentricity (graph theory) of a v ...

of 0.237.

Name

The moon was named in April 2007 after

Ægir Ægir (anglicised as Aegir; Old Norse 'sea'), Hlér (Old Norse 'sea'), or Gymir (Old Norse less clearly 'sea, engulfer'), is a jötunn and a personification of the sea in Norse mythology. In the Old Norse record, Ægir hosts the gods in his halls ...

, a giant from

Norse mythology Norse, Nordic, or Scandinavian mythology is the body of myths belonging to the North Germanic peoples, stemming from Old Norse religion and continuing after the Christianization of Scandinavia, and into the Nordic folklore of the modern period ...

, the personification of tranquil seas, the one who soothes storms away. He is a son of

Fornjót Fornjót (Old Norse: ''Fornjótr'') is a jötunn in Norse mythology, and the father of Hlér ('sea'), Logi ('fire') and Kári ('wind'). It is also the name of a legendary king of " Finnland and Kvenland". The principal study of this figure is ...

, and brother of

Logi Logi may refer to: People * Logi Bergmann Eiðsson (born 1966), Icelandic television host, news anchor and reporter * Logi Geirsson (born 1982), Icelandic handball player * Logi Gunnarsson (born 1981), Icelandic basketball player * Logi Jes Kr ...

(fire, flame) and Kári (wind). The exoplanet

Epsilon Eridani b Epsilon Eridani b, also known as AEgir ,There is some question on whether the name should be spelled (with an æ ligature), but the official press release from the IAU has . is an exoplanet approximately 10.5 light-years away orbiting the star E ...

(AEgir) was also named after this figure in 2015. The name may be pronounced various ways. (with the 'g' pronounced as a ''y''-sound) approximates modern Norwegian and Icelandic. (with a hard 'g') approximates what the

Old Norse Old Norse, Old Nordic, or Old Scandinavian, is a stage of development of North Germanic languages, North Germanic dialects before their final divergence into separate Nordic languages. Old Norse was spoken by inhabitants of Scandinavia and t ...

may have sounded like, while the Latinized/spelling pronunciations , and are also found.Harold Stanford (1922) ''The Standard Reference Work: For the Home, School and Library''

References

External links

T. Denk's Aegir website

May 4, 2005 (discovery)

May 3, 2005 (discovery and ephemeris)

April 5, 2007 (naming the moon) {{DEFAULTSORT:Aegir (Moon) Norse group Moons of Saturn Irregular satellites Discoveries by Scott S. Sheppard Astronomical objects discovered in 2005 Moons with a retrograde orbit