Space · Moons

Ymir

A moon of Saturn — Namesake of the Norse-group retrograde outer irregulars of Saturn.

Quick facts

Parent planet

Saturn

Diameter (mean)

18 km

Mass

3.97 × 10¹⁵ kg
5.4e-08 Moon masses

Mean orbital radius

23,040,000 km

Orbital period

1315.4 Earth days

Discovery year

2000

Discoverer

Brett J. Gladman et al.

Naming origin

Primordial Norse giant

Surface conditions

Ymir is a small retrograde outer irregular moon, namesake of Saturn's Norse group of outer satellites — moons orbiting Saturn backward at extreme inclinations and named for Norse mythology.

Missions and observations

Every Saturn-system mission has had an opportunity to image or characterize Ymir. The list below is the Saturn-system mission catalog; specific Ymir encounters are documented in mission archives.

Mission Year at Saturn Status

Pioneer 11

NASA

1979 Completed

Voyager 1

NASA

1980 Completed

Voyager 2

NASA

1981 Completed

Cassini-Huygens

NASA/ESA/ASI

2004 Completed

Dragonfly

NASA

2034 On the way

Naming etymology

Ymir was the primordial frost giant of Norse mythology, from whose body the world was formed after Odin and his brothers slew him. Adopted by the IAU in 2003.

Methodology & sources

Diameter, mass, and orbital parameters from JPL Solar System Dynamics — Physical Parameters. Discovery year and discoverer from the JPL Satellite Discovery Circumstances. Naming etymology from the IAU Working Group for Planetary System Nomenclature. Stylized SVG hero composed from NASA / JPL imagery as visual reference; no photographs are reproduced.

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