Anthe is a very small natural satellite

Natural satellite

A natural satellite or moon is a celestial body that orbits a planet or smaller body, which is called its primary. The two terms are used synonymously for non-artificial satellites of planets, of dwarf planets, and of minor planets....

 of Saturn

Saturn

Saturn is the sixth planet from the Sun and the second largest planet in the Solar System, after Jupiter. Saturn is named after the Roman god Saturn, equated to the Greek Cronus , the Babylonian Ninurta and the Hindu Shani. Saturn's astronomical symbol represents the Roman god's sickle.Saturn,...

 lying between the orbits of Mimas

Mimas (moon)

Mimas is a moon of Saturn which was discovered in 1789 by William Herschel. It is named after Mimas, a son of Gaia in Greek mythology, and is also designated Saturn I....

 and Enceladus

Enceladus (moon)

Enceladus is the sixth-largest of the moons of Saturn. It was discovered in 1789 by William Herschel. Until the two Voyager spacecraft passed near it in the early 1980s very little was known about this small moon besides the identification of water ice on its surface...

. It is also known as Saturn XLIX; its provisional designation was S/2007 S 4. It is named after one of the Alkyonides

Alkyonides

The Alkyonides were, in Greek mythology, the seven daughters of Alcyoneus. When their father was slain by Heracles, they threw themselves into the sea, and were transformed into halcyons by Amphitrite...

; the name means flowery. It is the sixtieth confirmed moon of Saturn.

It was discovered by the Cassini Imaging Team in images taken on May 30, 2007. Once the discovery was made, a search of older Cassini images revealed this small satellite in observations from as far back as June 2004. It was first announced on July 18, 2007.

Anthe is visibly affected by a perturbing mean-longitude resonance

Orbital resonance

In celestial mechanics, an orbital resonance occurs when two orbiting bodies exert a regular, periodic gravitational influence on each other, usually due to their orbital periods being related by a ratio of two small integers. Orbital resonances greatly enhance the mutual gravitational influence of...

 with the much larger Mimas. This causes its osculating orbit

Osculating orbit

In astronomy, and in particular in astrodynamics, the osculating orbit of an object in space is the gravitational Kepler orbit In astronomy, and in particular in astrodynamics, the osculating orbit of an object in space (at a given moment of time) is the gravitational Kepler orbit In astronomy,...

al elements to vary with an amplitude of about 20 km in semi-major axis on a timescale of about 2 Earth years. The close proximity to the orbits of Pallene

Pallene (moon)

Pallene is a very small natural satellite of Saturn. It is one of three small moons known as the Alkyonides that lie between the orbits of the larger Mimas and Enceladus. It is also designated as '.-Discovery:...

 and Methone

Methone (moon)

Methone is a very small natural satellite of Saturn lying between the orbits of Mimas and Enceladus.It was first seen by the Cassini Imaging Team and given the temporary designation '. Methone is also named '....

suggests that these moons may form a dynamical family.

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