Samiksha Jaiswal (Editor)

Shepherd moon

Updated on
Edit
Like
Comment
Share on FacebookTweet on TwitterShare on LinkedInShare on Reddit
Shepherd moon wwwdaviddarlinginfoimagesshepherdmoonsjpg

Enya 1991 shepherd moons 01 shepherd moons


A shepherd moon (also herder moon, watcher moon) is a small natural satellite that clears a gap in planetary-ring material or keeps particles within a ring contained. The name is a result of the fact they limit the "herd" of the ring particles as a shepherd.

Contents

Shepherd moon Shepherd Moons JungleKeycom Image

Due to their gravitational effect, they pick up particles and deflect them from their original orbits through orbital resonance. This causes gaps in the ring system, such as the particularly striking Cassini Division, as well as other characteristic bands, or strange "twisted" deformation of rings.

Shepherd moon Origin of Saturn39s F Ring and its shepherd moons revealed

Enya shepherd moons


Jupiter

Shepherd moon Moons of Saturn Shepherd Moons

Several of Jupiter's small innermost moons, namely Metis and Adrastea, are within Jupiter's ring system and are also within Jupiter's Roche limit. It is possible that these rings are composed of material that is being pulled off these two bodies by Jupiter's tidal forces, possibly facilitated by impacts of ring material on their surfaces.

Saturn

Shepherd moon Shepherd Moon FaceOff Universe Today

The complex ring system of Saturn has several such satellites. These include Prometheus (F ring), Daphnis (Keeler Gap), Pan (Encke Gap), Janus, and Epimetheus (both A ring).

Uranus

Shepherd moon Shepherd Moons of Saturn

Uranus also has shepherd moons on its ε ring, Cordelia and Ophelia. They are interior and exterior shepherds, respectively. Both moons are well within Uranus's synchronous orbit radius, and their orbits are therefore slowly decaying due to tidal deceleration.

Neptune

Shepherd moon Saturn39s shepherd moon Space and Astronomy news daily SpaceInfo

Neptune's rings are very unusual in that they first appeared to be composed of incomplete arcs in Earth-based observations, but Voyager 2's images showed them to be complete rings with bright clumps. It is thought that the gravitational influence of the shepherd moon Galatea and possibly other as-yet undiscovered shepherd moons are responsible for this clumpiness.

Minor planets

Shepherd moon The F ring and its two shepherd moons Pandora and Prometheus as

Rings around some centaurs have been identified. Chariklo's rings are remarkably well-defined and are suspected to either be very young or kept in place by a shepherd moon similar in mass to the rings. Chiron is also thought to have rings similar in form to those of Chariklo.

Shepherd moon Moons of Saturn Shepherd Moons

Shepherd moon Saturn39s Shepherd Moons

References

Shepherd moon Wikipedia