Gridr (Saturn LIV), originally known as S/2004 S 20, is a
natural satellite of
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 9 times that of Earth. It has an eighth the average density of Earth, but is over 95 tim ...
. Its discovery was announced by
Scott S. Sheppard,
David C. Jewitt, and
Jan Kleyna on October 7, 2019 from observations taken between December 12, 2004 and March 22, 2007.
It was given its permanent designation in June 2021.
On 24 August 2022, it was officially named after
Gríðr, a
jötunn in Norse mythology. She is the mother of
Víðarr the silent and the consort of
Odin
Odin (; from ) is a widely revered god in Norse mythology and Germanic paganism. Most surviving information on Odin comes from Norse mythology, but he figures prominently in the recorded history of Northern Europe. This includes the Roman Em ...
. She warned
Thor about the treachery of
Geirröðr and equipped him with her belt of strength, her iron glove, and her staff ''Gríðarvöl'' (Gríðr's-staff).
Gridr is about 4 kilometres in diameter, and orbits Saturn at an average distance of 19.418 Gm in 1010.55 days, at an inclination of 163° to the ecliptic, in a retrograde direction and with an eccentricity of 0.197.
References
Norse group
Irregular satellites
Moons of Saturn
Discoveries by Scott S. Sheppard
Astronomical objects discovered in 2019
Moons with a retrograde orbit
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