"Spencer Jones, was active in an international project for determining the solar parallax through observations of the minor planet Eros. In the second half of the twentieth century Alan Cousins set up very precise southern standards for UBV and introduced a widely used system of VRI photometry that enjoyed international recognition for precision. In 1977 the occultation of the star SAO 158687 was observed by Joseph Churms from the former Royal Observatory and these observations provided needed confirmation of the Uranian rings discovered from the Kuiper aeroplane by Elliot et al. During the 19th century the Observatory was regarded as"
"the more extensive set around Saturn and the simpler systems around Jupiter and Neptune. The rings of Uranus were discovered on March 10, 1977, by James L. Elliot, Edward W. Dunham, and Douglas J. Mink. More than 200 years ago, William Herschel also reported observing rings, but modern astronomers are skeptical that he could actually have noticed them, as they are very dark and faint. 1977 Upsilon mesons 1977 Bottom quark 1978 Restriction endonucleases 1978 Charon 1979 Metis 1979 Thebe 1979 Rings of Jupiter 1980 Oncogene 1980 Pandora 1980 Prometheus 1980 Atlas 1981 Larissa 1983 Pneumococcal polysaccharide vaccine 1984 ""Whydah"""
"the ring formation and active movement was understood. The rings are not a series of tiny ringlets as many think, but are more of a disk with varying density. They consist mostly of water ice and trace amounts of rock, and the particles range in size from micrometers to meters. Uranus' ring system lies between the level of complexity of Saturn's vast system and the simpler systems around Jupiter and Neptune. They were discovered in 1977 by James L. Elliot, Edward W. Dunham, and Jessica Mink. In the time between then and 2005, observations by ""Voyager 2"" and the Hubble"
"most active ring in the Solar System, with features changing on a timescale of hours. It is located 3,000 km beyond the outer edge of the A ring. The ring was discovered in 1979 by the Pioneer 11 imaging team. It is very thin, just a few hundred km in radial extent. While the traditional view has been that it is held together by two shepherd moons, Prometheus and Pandora, which orbit inside and outside it, recent studies indicate that only Prometheus contributes to the confinement. Numerical simulations suggest the ring was formed when Prometheus and Pandora collided with each"
"pieces of debris that formed as a result of those impacts, only a few particles survived, in stable zones corresponding to the locations of the present rings. William Herschel described a possible ring around Uranus in 1789. This sighting is generally considered doubtful, because the rings are quite faint, and in the two following centuries none were noted by other observers. Still, Herschel made an accurate description of the epsilon ring's size, its angle relative to Earth, its red colour, and its apparent changes as Uranus travelled around the Sun. The ring system was definitively discovered on 10 March 1977"
"G ring. Voyager 2's closest approach occurred in August 1981 at a distance of 41,000 km. Voyager 2's working photopolarimeter allowed it to observe the ring system at higher resolution than Voyager 1, and to thereby discover many previously unseen ringlets. ""Cassini"" spacecraft entered into orbit around Saturn in July 2004. ""Cassini"" images of the rings are the most detailed to-date, and are responsible for the discovery of yet more ringlets. The rings are named alphabetically in the order they were discovered. The main rings are, working outward from the planet, C, B and A, with the Cassini Division, the"
"serious doubt on whether Herschel could have seen anything of the sort while hundreds of other astronomers saw nothing. It has been claimed that Herschel gave accurate descriptions of the ε ring's size relative to Uranus, its changes as Uranus travelled around the Sun, and its color. The definitive discovery of the Uranian rings was made by astronomers James L. Elliot, Edward W. Dunham, and Jessica Mink on March 10, 1977, using the Kuiper Airborne Observatory, and was serendipitous. They planned to use the occultation of the star SAO 158687 by Uranus to study the planet's atmosphere. When their observations"
"fossilized bone out of the corner of his eye, and recognized it as hominid. Later described as the first known member of ""Australopithecus afarensis"". Dr. Johanson's girlfriend suggested she be named ""Lucy"" after the Beatles' song ""Lucy in the Sky with Diamonds"" which was played repeatedly during the night of the discovery. 1974 J/ψ mesons 1974 Charm quark 1974 Binary pulsars 1974 Leda 1974 Seaborgium 1975 1983 Bok 1975 Themisto 1975 Amarillo Starlight 1976 D mesons 1976 Hepatitis B virus vaccine 1977 Tau lepton 1977 Rings of Uranus The planet Uranus has a system of rings intermediate in complexity between"
"responsible for the magnetic effects that had led to the ring hypothesis. It had been theorized by some astronomers that Pluto might have a ring system. However, this possibility has been ruled out by ""New Horizons"", which would have detected any such ring system. 10199 Chariklo, a centaur, was the first minor planet discovered to have rings. It has two rings, perhaps due to a collision that caused a chain of debris to orbit it. The rings were discovered when astronomers observed Chariklo passing in front of the star UCAC4 248-108672 on June 3, 2013 from seven locations in South"
"by the ""Galileo"" orbiter in the 1990s. Its four main parts are a faint thick torus known as the ""halo""; a thin, relatively bright main ring; and two wide, faint ""gossamer rings"". The system consists mostly of dust. Saturn's rings are the most extensive ring system of any planet in the Solar System, and thus have been known to exist for quite some time. Galileo Galilei first observed them in 1610, but they were not accurately described as a disk around Saturn until Christiaan Huygens did so in 1655. With help from the NASA/ESA/ASI Cassini mission, a further understanding of"
"simultaneously serving as sources of the dust. The rings were investigated in detail during the ""Voyager 2"" spacecraft's flyby of Neptune in August 1989. They were studied with optical imaging, and through observations of occultations in ultraviolet and visible light. The spaceprobe observed the rings in different geometries relative to the Sun, producing images of back-scattered, forward-scattered and side-scattered light. Analysis of these images allowed derivation of the phase function (dependence of the ring's reflectivity on the angle between the observer and Sun), and geometrical and Bond albedo of ring particles. Analysis of Voyager's images also led to discovery of"
"team of astronomers using ten telescopes at various locations in Argentina, Brazil, and Chile in South America during observation of a stellar occultation on 3 June 2013, and was announced on 26 March 2014. The existence of a ring system around a minor planet was unexpected because it had been thought that rings could only be stable around much more massive bodies. Ring systems around minor bodies had not previously been discovered despite the search for them through direct imaging and stellar occultation techniques. Chariklo's rings should disperse over a period of at most a few million years, so either"
"organics processed by radiation, like in the rings of Uranus. 20 to 70 percent of the rings are dust, a relatively high proportion. Hints of the rings were seen for decades prior to their conclusive discovery by ""Voyager 2"" in 1989. Reports in March 2008 suggested that Saturn's moon Rhea may have its own tenuous ring system, which would make it the only moon known to have a ring system. A later study published in 2010 revealed that imaging of Rhea by the ""Cassini"" spacecraft was inconsistent with the predicted properties of the rings, suggesting that some other mechanism is"
"high-energy particles, were detected at the outer edge of the magnetosphere of Jupiter. The two Voyager space probes made a number of important discoveries about Jupiter, its satellites, its radiation belts, and its never-before-seen planetary rings. The gravitational assist trajectories at Jupiter were successfully carried out by both Voyagers, and the two spacecraft went on to visit Saturn and its system of moons and rings. ""Voyager 1"" encountered Saturn in November 1980, with the closest approach on November 12, 1980, when the space probe came within of Saturn's cloud-tops. The space probe's cameras detected complex structures in the rings of"
"six inner moons of Neptune, including the Adams ring shepherd Galatea. ""*A question mark means that the parameter is not known."" Rings of Neptune The rings of Neptune consist primarily of five principal rings and were first discovered (as ""arcs"") on 22 July 1984 in Chile by Patrice Bouchet, Reinhold Häfner and Jean Manfroid at La Silla Observatory (ESO) during an observing program proposed by André Brahic and Bruno Sicardy from Paris Observatory, and at Cerro Tololo Interamerican Observatory by F. Vilas and L.-R. Elicer for a program led by William Hubbard. They were eventually imaged in 1989 by the"
"1977 Shura 1977 Shura, provisional designation , is a stony asteroid from the middle region of the asteroid belt, approximately 16 kilometers in diameter. It was discovered on 30 August 1970, by Russian astronomer Tamara Smirnova at the Crimean Astrophysical Observatory, Nauchnyj, on the Crimean peninsula. The asteroid was named for Soviet Aleksandr Kosmodemyansky. ""Shura"" orbits the Sun in the central main-belt at a distance of 2.6–3.0 AU once every 4 years and 8 months (1,694 days). Its orbit has an eccentricity of 0.07 and an inclination of 8° with respect to the ecliptic. The asteroid was first observed as"
"in honor of a friend of the discoverer. 771 Libera 771 Libera, provisional designation 1913 TO, is a metallic asteroid from the middle region of the asteroid belt, about 29 kilometers in diameter. It was discovered by Austrian astronomer Joseph Rheden at the Vienna Observatory in Austria, on 21 November 1913. The metallic X-type asteroid orbits the Sun at a distance of 2.0–3.3 AU once every 4 years and 4 months (1,576 days). Its orbit shows an eccentricity of 0.25 and is tilted by 15 degrees to the plane of the ecliptic. A photometric observation of the asteroid's light-curve performed"
"followed by ""Voyager 2"", which made its closest approach on July 9, 1979, 576,000 km away from the planet's cloud tops. The probe discovered Jupiter's ring, observed intricate vortices in its atmosphere, observed active volcanoes on Io, a process analogous to plate tectonics on Ganymede, and numerous craters on Callisto. The ""Voyager"" missions vastly improved our understanding of the Galilean moons, and also discovered Jupiter's rings. They also took the first close-up images of the planet's atmosphere, revealing the Great Red Spot as a complex storm moving in a counter-clockwise direction. Other smaller storms and eddies were found throughout the"
"the Minor Planet Center before November 1977 (). 2063 Bacchus 2063 Bacchus ( ), provisional designation , is a stony asteroid and near-Earth object of the Apollo group, approximately 1 kilometer in diameter. The contact binary was discovered on 24 April 1977, by American astronomer Charles Kowal at the Palomar Observatory in California, United States. It was named after Bacchus from Roman mythology. ""Bacchus"" orbits the Sun at a distance of 0.7–1.5 AU once every 1 years and 1 month (409 days). Its orbit has an eccentricity of 0.35 and an inclination of 9° with respect to the ecliptic. The"
"of Allegheny Observatory and Aristarkh Belopolsky of Pulkovo Observatory showed Maxwell's analysis was correct. Four robotic spacecraft have observed Saturn's rings from the vicinity of the planet. Pioneer 11's closest approach to Saturn occurred in September 1979 at a distance of 20,900 km. Pioneer 11 was responsible for the discovery of the F ring. Voyager 1's closest approach occurred in November 1980 at a distance of 64,200 km. A failed photopolarimeter prevented Voyager 1 from observing Saturn's rings at the planned resolution; nevertheless, images from the spacecraft provided unprecedented detail of the ring system and revealed the existence of the"
"1877 Marsden 1877 Marsden, provisional designation , is a carbonaceous Hildian asteroid from the outermost region of the asteroid belt, approximately 35 kilometers in diameter. It was discovered during the Palomar–Leiden Trojan survey in 1971, and named after British astronomer Brian Marsden. ""Marsden"" was discovered on 24 March 1971, by Dutch astronomer couple Ingrid and Cornelis van Houten at Leiden, on photographic plates taken by Dutch–American astronomer Tom Gehrels at Palomar Observatory, California. The discovery was made in a survey of faint Trojans (in spite of not having received a typical T-1 designation). The trio of Dutch and Dutch–American astronomers"
"rings via shepherding. In 2003, Showalter and Jack J. Lissauer discovered two new moons of Uranus (Mab and Cupid) in Hubble Space Telescope images. In 2006, they announced the discovery of two very faint rings, the μ and ν rings, within the same data. In 2010, Showalter discovered that spiral vertical corrugations in Jupiter's rings were caused by the impact of Comet Shoemaker–Levy 9 in July 1994. A second smaller set of corrugations appear to be consistent with an unknown impact in early 1990. He and co-researchers also found similar spiral patterns in Saturn's D Ring. Showalter has assisted the"
"12373 Lancearmstrong 12373 Lancearmstrong, provisional designation , is a bright Vestian asteroid from the inner regions of the asteroid belt, approximately in diameter. It was discovered on 15 May 1994, by American astronomer and software engineer Charles de Saint-Aignan after examining films taken at Palomar Observatory, California, and named after American cyclist Lance Armstrong. The asteroid orbits the Sun in the inner main-belt at a distance of 2.2–2.7 AU once every 3 years and 10 months (1,401 days). Its orbit has an eccentricity of 0.11 and an inclination of 7° with respect to the ecliptic. The body's observation arc begins"
"AU) from its centre is considered to be indirect evidence of the existence of an exomoon with mass up to 0.8 Earth masses. J1407b is the first exoplanet or brown dwarf discovered with a ring system by the transit method. A sequence of occultations (eclipses) of the star occurred over a 56-day period in 2007. The pattern was consistent with that expected for the transit of a large array of multiple rings, indicating the substellar companion dubbed “J1407b”. The J1407b ring system has an outer radius of approximately 90 million km (about 640 times the extent of Saturn’s rings). Cleared"
"Rings of Rhea The Saturnian moon Rhea may have a tenuous ring system consisting of three narrow, relatively dense bands within a particulate disk. This would be the first discovery of rings around a moon. The potential discovery was announced in the journal ""Science"" on March 6, 2008. In November 2005 the ""Cassini"" orbiter found that Saturn's magnetosphere is depleted of energetic electrons near Rhea. According to the discovery team, the pattern of depletion is best explained by assuming the electrons are absorbed by solid material in the form of an equatorial disk of particles perhaps several decimeters to approximately"
"WASP-17. The discovery of the J1407 system and its unusual eclipses were first reported by a team led by University of Rochester astronomer Eric Mamajek in 2012. The existence and parameters of the ring system around the substellar companion J1407b were deduced from the observation of a very long and complex eclipse of the previously anonymous star J1407 during a 56-day period during April and May 2007. The low-mass companion J1407b has been referred to as a ""Saturn on steroids"" or “Super Saturn” due to its massive system of circumplanetary rings with a radius of approximately 90 million km (0.6"
"Rings of Neptune The rings of Neptune consist primarily of five principal rings and were first discovered (as ""arcs"") on 22 July 1984 in Chile by Patrice Bouchet, Reinhold Häfner and Jean Manfroid at La Silla Observatory (ESO) during an observing program proposed by André Brahic and Bruno Sicardy from Paris Observatory, and at Cerro Tololo Interamerican Observatory by F. Vilas and L.-R. Elicer for a program led by William Hubbard. They were eventually imaged in 1989 by the ""Voyager 2"" spacecraft. At their densest, they are comparable to the less dense portions of Saturn's main rings such as the"
"771 Libera 771 Libera, provisional designation 1913 TO, is a metallic asteroid from the middle region of the asteroid belt, about 29 kilometers in diameter. It was discovered by Austrian astronomer Joseph Rheden at the Vienna Observatory in Austria, on 21 November 1913. The metallic X-type asteroid orbits the Sun at a distance of 2.0–3.3 AU once every 4 years and 4 months (1,576 days). Its orbit shows an eccentricity of 0.25 and is tilted by 15 degrees to the plane of the ecliptic. A photometric observation of the asteroid's light-curve performed at the Palmer Divide Observatory during 1999 rendered"
"Center before November 1977 (). 1981 Midas 1981 Midas, provisional designation , is a vestoid asteroid, classified as a near-Earth object and potentially hazardous asteroid, approximately 2 kilometers in diameter. It was discovered on 6 March 1973, by American astronomer Charles Kowal at Palomar Observatory in San Diego County, California. It was named after King Midas from Greek mythology. The moderately bright V-type asteroid is also an Apollo asteroid, as well as a Venus and Mars-crosser. The asteroid orbits the Sun at a distance of 0.6–2.9 AU once every 2 years and 4 months (864 days). Its orbit has an"
"of Saturn's orbit, or roughly the ecliptic, and thus is tilted 27 degrees from Saturn's equatorial plane and the other rings. Phoebe is inclined by 5° with respect to Saturn's orbit plane (often written as 175°, due to Phoebe's retrograde orbital motion), and its resulting vertical excursions above and below the ring plane agree closely with the ring's observed thickness of 40 Saturn radii. The existence of the ring was proposed in the 1970s by Steven Soter. The discovery was made by Anne J. Verbiscer and Michael F. Skrutskie (of the University of Virginia) and Douglas P. Hamilton (of the"
"moon Himalia, 170 kilometres in diameter, creating a faint ring. This possible ring appears as a faint streak near Himalia in images from NASA's ""New Horizons ""mission to Pluto. This suggests that Jupiter sometimes gains and loses small moons through collisions. However, the recovery of Dia in 2010 and 2011 disproves the link between Dia and the Himalia ring, although it is still possible that a different moon may have been involved. The existence of the Jovian rings was inferred from observations of the planetary radiation belts by Pioneer 11 spacecraft in 1975. In 1979 the ""Voyager 1"" spacecraft obtained"
"Leo Ring The Leo Ring is an immense intergalactic cloud of hydrogen and helium gas some in diameter, in orbit of two galaxies, in the center of the Leo Group of galaxies, within the constellation of Leo. Radio astronomers discovered the cloud in 1983. Astronomers had theorized that the ring was primordial gas in the process of forming a galaxy. The GALEX satellite detected ultraviolet emissions that astronomers at Johns Hopkins University and the Carnegie Institution for Science interpret to indicate star creation in newly forming dwarf galaxies in a 19 February 2009 ""Nature"" paper. In 2010, it was found"
"77 Frigga Frigga ( ; minor planet designation: 77 Frigga) is a large, M-type, possibly metallic main-belt asteroid. It was discovered by C. H. F. Peters on November 12, 1862. It is named after Frigg, the Norse goddess. Frigga has been studied by radar. The spectra of this asteroid displays a feature at a wavelength of 3 μm, indicating the presence of hydrated minerals on the surface. The near infrared spectrum is reddish and shows no spectral absorption features. Potential analogs of this spectrum include enstatite chondrites and nickel-iron meteorites. Since 1999 there have been four stellar occultations by the"