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"Methone is a very small natural satellite of Saturn orbiting between the orbits of Mimas and Enceladus. It was discovered in 2004, and in 2012 was imaged more closely by the Cassini orbiter probe. History Discovery image of Methone on 1 June 2004 Methone was first seen by the Cassini Imaging Team and given the temporary designation '. Methone is also named ' (32). The Cassini spacecraft made two visits to Methone and its closest approach was made on May 20, 2012 with a minimum distance of from it. The name Methone was approved by the IAU Working Group on Planetary System Nomenclature on January 21, 2005. It was ratified at the IAU General Assembly in 2006. Methone (Greek Μεθώνη) was one of the Alkyonides, the seven beautiful daughters of the Giant Alkyoneus. Orbit Methone's orbit is visibly affected by a perturbing 14:15 mean-longitude resonance with the much larger Mimas. This causes its osculating orbital elements to vary with an amplitude of about in semi-major axis, and 5° in longitude of its periapsis on a timescale of about 450 days. Its eccentricity also varies on different timescales between 0.0011 and 0.0037, and its inclination between about 0.003° and 0.020°. Physical characteristics In May 2012, the Cassini spacecraft obtained its first close-up photographs of Methone, revealing an egg-shaped moonlet with a remarkably smooth surface, with no visible craters. The moons Pallene and Aegaeon are thought to be similarly smooth. Methone has two different sharply defined albedo regions, one distinctly (~13%) darker centered on Methone's leading point. Its brighter area has an albedo of ~0.70. UV and IR spectra gave no indication of a color difference between the two regions, suggesting that a physical rather than compositional difference may be responsible. Increased exposure to electrons from Saturn's magnetosphere has been proposed to be responsible for thermal anomalies on the leading hemispheres of Mimas and Tethys, and a similar irradiation anisotropy might be behind Methone's albedo pattern. Methone's mean radius is . Assuming that Methone is in hydrostatic equilibrium, i.e. that its elongated shape simply reflects the balance between the tidal force exerted by Saturn and Methone's gravity, its density can be estimated: , among the lowest density values obtained or inferred for a Solar System body. This indicates that Methone is composed of icy fluff, material that might be mobile enough to explain the lack of craters. Relationship with Saturn's rings Material blasted off Methone by micrometeoroid impacts is believed to the source of the Methone Ring Arc, a faint partial ring around Saturn co-orbital with Methone that was discovered in September 2006. References Bibliography * External links * *Methone Profile by NASA's Solar System Exploration *IAU Working Group for Planetary System Nomenclature Category:Moons of Saturn 20040601 "
"'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 '. Discovery Discovery image of Pallene in 2004 from the Cassini probe Pallene was discovered by the Cassini Imaging Team in 2004, during the Cassini–Huygens mission. It was given the temporary designation '. In 2005, the name Pallene was provisionally approved by the IAU Division III Working Group for Planetary System Nomenclature, and was ratified at the IAU General Assembly in 2006. The name refers to Pallene, one of the Alkyonides, the seven beautiful daughters of the giant Alkyoneus. After the discovery in 2004, it was realized that Pallene had been first photographed on August 23, 1981, by the space probe '. It had appeared in a single photograph and had been provisionally named ' and estimated to orbit 200,000 km from Saturn. Because it had not been visible in other images, it had not been possible to compute its orbit at the time, but recent comparisons have shown it to match Pallene's orbit. Orbital characteristics Pallene is visibly affected by a perturbing mean-longitude resonance with the much larger Enceladus, although this effect is not as large as Mimas's perturbations on Methone. The perturbations cause Pallene's osculating orbital elements to vary with an amplitude of about 4 km in semi-major axis, and 0.02° in longitude (corresponding to about 75 km). Eccentricity also changes on various timescales between 0.002 and 0.006, and inclination between about 0.178° and 0.184°. Ring In 2006, images taken in forward-scattered light by the Cassini spacecraft enabled the Cassini Imaging Team to discover a faint dust ring around Saturn that shares Pallene's orbit, now named the Pallene Ring. The ring has a radial extent of about 2,500 km. Its source is particles blasted off Pallene's surface by meteoroid impacts, which then form a diffuse ring around its orbital path. Exploration The Cassini spacecraft, which studied Saturn and its moons until September, 2017, performed a fly-by of Pallene on 16 October 2010, and 14 September 2011 at a distance of 36,000 kilometers (22,000 miles) and 44,000 kilometers respectively. References Further reading External links * *Pallene Profile by NASA's Solar System Exploration Category:Moons of Saturn 20040601 "
"LRB may refer to: * Love Runs Blind, a Bangladeshi rock band * Lego Rock Band, a game in the Rock Band video game series * Liquid rocket booster * Little Red Book, quotations from Chairman Mao * Little River Band, an Australian music act * London Review of Books, a British journal of literary and intellectual essays See also *L:RB, stock symbol for the consumer goods company Reckitt Benckiser "