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Suttungr (moon)
Suttungr , or Saturn XXIII, is a natural satellite of Saturn. It was discovered by Brett J. Gladman, et al. in 2000, and given the temporary designation S/2000 S 12. It was named for Suttungr in Norse mythology, a Jötunn or giant who once owned the mead of poetry. Suttungr is about 7 kilometres in diameter, and orbits Saturn at an average distance of 19,667 Mm in 1029.703 days. It may have formed from debris knocked off Phoebe. The Suttung orbit is retrograde, at an inclination of 174° to the ecliptic (151° to Saturn's equator) and with an eccentricity of 0.131. Its rotation period is hours, and like Albiorix its light curve exhibits two minima at certain angles, and three minima at others. Having a similar gray color and orbit as Thrymr, the two moons may be members of the same dynamical family. Its name was announced in its oblique form Suttung iIAU Circular 8177 However, the IAU Working Group on Planetary System Nomenclature later decided to add the nomi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eccentricity (orbit)
In astrodynamics, the orbital eccentricity of an astronomical object is a dimensionless parameter that determines the amount by which its orbit around another body deviates from a perfect circle. A value of 0 is a circular orbit, values between 0 and 1 form an elliptic orbit, 1 is a parabolic escape orbit (or capture orbit), and greater than 1 is a hyperbola. The term derives its name from the parameters of conic sections, as every Kepler orbit is a conic section. It is normally used for the isolated two-body problem, but extensions exist for objects following a rosette orbit through the Galaxy. Definition In a two-body problem with inverse-square-law force, every orbit is a Kepler orbit. The eccentricity of this Kepler orbit is a non-negative number that defines its shape. The eccentricity may take the following values: * circular orbit: ''e'' = 0 * elliptic orbit: 0 < ''e'' < 1 * [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Discoveries By Brett J
Discoveries may refer to: Music * ''Discoveries'' (Cannonball Adderley album), 1955 * ''Discoveries'' (Josh Nelson album), 2011 * ''Discoveries'' (Northlane album), 2011 Other uses * ''Discoveries'' (film), a 1939 British film * Discoveries (horse), a racehorse * ''Discoveries'' (Robertson Davies), a 2002 book by Robertson Davies * ''Discoveries'' (TV series), a Canadian youth science television series which aired on CBC Television in 1957 * ''Abrams Discoveries'', a series of illustrated non-fiction books published by Harry N. Abrams * ''Discoveries'', a work by William Butler Yeats, written in 1907 * ''Discoveries'', a magazine published by Cedars-Sinai Medical Center See also * Age of Discoveries * Discovery (other) * Explorations (other) Explorations may refer to: *The plural of exploration Exploration refers to the historical practice of discovering remote lands. It is studied by geographers and historians. Two major eras of exploration occu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Irregular Satellites
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 satellites, which formed in orbit around them. Irregular moons have a stable orbit, unlike temporary satellites which often have similarly irregular orbits but will eventually depart. The term does not refer to shape as Triton is a round moon, but is considered irregular due to its orbit. As of December 2022, 149 irregular moons are known, orbiting all four of the outer planets (Jupiter, Saturn, Uranus and Neptune). The largest of each planet are Himalia of Jupiter, Phoebe of Saturn, Sycorax of Uranus, and Triton of Neptune. It is currently thought that the irregular satellites were captured from heliocentric orbits near their current locations, shortly after the formation of their parent planet. An alternative theory, that they orig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moons Of Saturn
The moons of Saturn are numerous and diverse, ranging from tiny moonlets only tens of meters across to enormous Titan, which is larger than the planet Mercury. Saturn has 83 moons with confirmed orbits that are not embedded in its rings—of which only 13 have diameters greater than 50 kilometers—as well as dense rings that contain millions of embedded moonlets and innumerable smaller ring particles. Seven Saturnian moons are large enough to have collapsed into a relaxed, ellipsoidal shape, though only one or two of those, Titan and possibly Rhea, are currently in hydrostatic equilibrium. Particularly notable among Saturn's moons are Titan, the second- largest moon in the Solar System (after Jupiter's Ganymede), with a nitrogen-rich Earth-like atmosphere and a landscape featuring dry river networks and hydrocarbon lakes, Enceladus, which emits jets of gas and dust from its south-polar region, and Iapetus, with its contrasting black and white hemispheres. Twenty-four of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Norse Group
The Norse group is a large group of retrograde irregular satellites of Saturn. Their semi-major axes range between 12 and 24 Gm, their inclinations between 136° and 175° and their eccentricities between 0.13 and 0.77. Unlike for the Inuit and Gallic groups, the orbital parameters are widely dispersed and group is likely to be composed from a number of subgroups with more homogenous orbital and physical parameters. For example, the satellites with inclinations around 174 degrees alone are thought to comprise at least two subgroups. Eight other moons form the Skathi subgroup. Their semi-major axes range between 15 and 20 Gm, their inclinations between 147° and 158°. Narvi forms a separate subgroup with Bestla. The International Astronomical Union (IAU) reserves names taken from Norse mythology (mostly giants) for these moons. The exception is Phoebe (Greek mythology), the largest, which was discovered long before the others. The discovery of 17 new moons in this group was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nominative Case
In grammar, the nominative case ( abbreviated ), subjective case, straight case or upright case is one of the grammatical cases of a noun or other part of speech, which generally marks the subject of a verb or (in Latin and formal variants of English) the predicate noun or predicate adjective, as opposed to its object or other verb arguments. Generally, the noun "that is doing something" is in the nominative, and the nominative is often the form listed in dictionaries. Etymology The English word ''nominative'' comes from Latin ''cāsus nominātīvus'' "case for naming", which was translated from Ancient Greek ὀνομαστικὴ πτῶσις, ''onomastikḗ ptôsis'' "inflection for naming", from ''onomázō'' "call by name", from ''ónoma'' "name". Dionysius Thrax in his The Art of Grammar refers to it as ''orthḗ'' or ''eutheîa'' "straight", in contrast to the oblique or "bent" cases. Characteristics The reference form (more technically, the ''least marked'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Working Group On Planetary System Nomenclature
The International Astronomical Union (IAU; french: link=yes, Union astronomique internationale, UAI) is a nongovernmental organisation with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreach, education, and development through global cooperation. It was founded in 1919 and is based in Paris, France. The IAU is composed of individual members, who include both professional astronomers and junior scientists, and national members, such as professional associations, national societies, or academic institutions. Individual members are organised into divisions, committees, and working groups centered on particular subdisciplines, subjects, or initiatives. As of 2018, the Union had over 13,700 individual members, spanning 90 countries, and 82 national members. Among the key activities of the IAU is serving as a forum for scientific conferences. It sponsors nine annual symposia and holds a triannual General Assembly that sets policy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oblique Case
In grammar, an oblique ( abbreviated ; from la, casus obliquus) or objective case (abbr. ) is a nominal case other than the nominative case, and sometimes, the vocative. A noun or pronoun in the oblique case can generally appear in any role except as subject, for which the nominative case is used. The term ''objective case'' is generally preferred by modern English grammarians, where it supplanted Old English's dative and accusative. When the two terms are contrasted, they differ in the ability of a word in the oblique case to function as a possessive attributive; whether English has an oblique rather than an objective case then depends on how " proper" or widespread one considers the dialects where such usage is employed. An oblique case often contrasts with an unmarked case, as in English oblique ''him'' and ''them'' versus nominative ''he'' and ''they''. However, the term ''oblique'' is also used for languages without a nominative case, such as ergative–absolutive la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrymr (moon)
Thrymr , or Saturn XXX, is a natural satellite of Saturn. It was discovered by Gladman and colleagues in 2000, and given the temporary designation S/2000 S 7. Its name comes from Norse mythology, where Thrymr is a Jotun. Thrymr is about 7 kilometres in diameter, and orbits Saturn at an average distance of 20,810 Mm in 1120.809 days. It may have formed from debris knocked off Phoebe. The Thrymian orbit is retrograde, at an inclination of 175° to the ecliptic (151° to Saturn's equator) and with an eccentricity of 0.453. Like Ijiraq and Kiviuq, Thrymr's orbit overlaps strongly with Phoebe's such that it is likely to collide with it in the future. Its rotation period is hours, the slowest among the retrograde moons measured by '' Cassini–Huygens'' and the second-slowest after Tarqeq. Having two maxima and two minima in its light curve, it may therefore be a contact binary, although this is less likely than for Kiviuq and Bestla. The surface of Thrymr is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Light Curve
In astronomy, a light curve is a graph of light intensity of a celestial object or region as a function of time, typically with the magnitude of light received on the y axis and with time on the x axis. The light is usually in a particular frequency interval or band. Light curves can be periodic, as in the case of eclipsing binaries, Cepheid variables, other periodic variables, and transiting extrasolar planets, or aperiodic, like the light curve of a nova, a cataclysmic variable star, a supernova or a microlensing event or binary as observed during occultation events. The study of the light curve, together with other observations, can yield considerable information about the physical process that produces it or constrain the physical theories about it. Variable stars Graphs of the apparent magnitude of a variable star over time are commonly used to visualise and analyse their behaviour. Although the categorisation of variable star types is increasingly done from t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
