Mneme , also known as , is a retrograde

irregular satellite In astronomy, an irregular moon, irregular satellite or irregular natural satellite is a natural satellite following a distant, inclined, and often eccentric and retrograde orbit. They have been captured by their parent planet, unlike regular s ...

Jupiter Jupiter is the fifth planet from the Sun and the largest in the Solar System. It is a gas giant with a mass more than two and a half times that of all the other planets in the Solar System combined, but slightly less than one-thousandth t ...

. It was discovered by teams of astronomers led by

Brett J. Gladman Brett James Gladman (born April 19, 1966) is a Canadian astronomer and a full professor at the University of British Columbia's Department of Physics and Astronomy in Vancouver, British Columbia. He holds the Canada Research Chair in planetary as ...

and

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 ...

in 2003, and was provisionally designated S/2003 J 21. Mneme is about 2 kilometres in diameter, and orbits Jupiter at an average distance of 21,427,000 kilometres in 640.769 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 reference plane and the orbital plane or axis of direction of the orbiting object. For a satellite orbiting the Eart ...

of 149° 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 agains ...

(148° to Jupiter's equator) 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-Centre (geometry), center, in geometry * Eccentricity (g ...

of 0.2214. Its average orbital speed is 2.43 km/s. It was named in March 2005 after

Mneme In Greek mythology, Mneme ( grc-gre, Μνήμη, Mnḗmē) was one of the three original Boeotian muses, along with her sisters Aoede and Melete before Arche and Thelxinoë were identified, increasing the number to five. Later, the Nine Olym ...

, one of the three original

Muse In ancient Greek religion and mythology, the Muses ( grc, Μοῦσαι, Moûsai, el, Μούσες, Múses) are the inspirational goddesses of literature, science, and the arts. They were considered the source of the knowledge embodied in the ...

s.IAUC 8502: ''Satellites of Jupiter''
2005 March 30 (naming the moon) She is sometimes confused with

Mnemosyne In Greek mythology and ancient Greek religion, Mnemosyne (; grc, Μνημοσύνη, ) is the goddess of memory and the mother of the nine Muses by her nephew Zeus. In the Greek tradition, Mnemosyne is one of the Titans, the twelve divine chil ...

, mother of the Muses (the three or the nine, depending on the author) by

Zeus Zeus or , , ; grc, Δῐός, ''Diós'', label= genitive Boeotian Aeolic and Laconian grc-dor, Δεύς, Deús ; grc, Δέος, ''Déos'', label= genitive el, Δίας, ''Días'' () is the sky and thunder god in ancient Greek reli ...

(Jupiter). Mneme belongs to the Ananke group, retrograde irregular moons which orbit Jupiter between 19.3 and 22.7 million kilometres, at inclinations of roughly 150°.

References

{{DEFAULTSORT:Mneme (Moon) Ananke group Moons of Jupiter Discoveries by Brett J. Gladman Discoveries by Scott S. Sheppard Irregular satellites 20030209 Moons with a retrograde orbit