Thyone , 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 a team of astronomers from the

University of Hawaii A university () is an institution of higher (or tertiary) education and research which awards academic degrees in several academic disciplines. Universities typically offer both undergraduate and postgraduate programs. In the United States, th ...

led 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 ...

in 2001, and given the temporary designation .MPEC 2002-J54: ''Eleven New Satellites of Jupiter''
2002 May (discovery and ephemeris) Thyone is about 4 kilometres in diameter, and orbits Jupiter at an average distance of 21,605,000 kilometres in 603.58 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 147.28° 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 ...

(146.93° 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 0.2526. Its average orbital speed is 2.43 km/s. It was named in August 2003 after Thyone, better known as

Semele Semele (; Ancient Greek: Σεμέλη ), in Greek mythology, was the youngest daughter of Cadmus and Harmonia, and the mother of Dionysus by Zeus in one of his many origin myths. Certain elements of the cult of Dionysus and Semele came from ...

, mother of

Dionysus In ancient Greek religion and myth, Dionysus (; grc, Διόνυσος ) is the god of the grape-harvest, winemaking, orchards and fruit, vegetation, fertility, insanity, ritual madness, religious ecstasy, festivity, and theatre. The Roma ...

Greek mythology A major branch of classical mythology, Greek mythology is the body of myths originally told by the ancient Greeks, and a genre of Ancient Greek folklore. These stories concern the origin and nature of the world, the lives and activities ...

.IAUC 8177: ''Satellites of Jupiter, Saturn, Uranus''
2003 August (naming the moon) Thyone belongs to the Ananke group, retrograde irregular moons which orbit Jupiter between 19.3 and 22.7 million kilometres, at inclinations of roughly 150°. Thyone-prediscovery-CFHT-annotated

References

{{DEFAULTSORT:Thyone (Moon) Ananke group Moons of Jupiter Discoveries by Scott S. Sheppard Irregular satellites 20011211 Moons with a retrograde orbit