There are seven known planets in this relatively nearby stellar system, and all are roughly the size of Earth.
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For astrobiologists, the Warm Zone is the most significant, as it represents the swath of space in a stellar system where life is likely to emerge.
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They believe Terzan 5 is really a stellar system that represents a fossilized relic of galaxy formation, perhaps one of the earliest building blocks of our galaxy.
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According to National Geographic, however, when exactly the stellar system will self-destruct is unclear: it could be this week or in tens of thousands of years.
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It likely formed in another stellar system altogether, was ejected who knows how long ago, and has been traveling interstellar space before a chance encounter with our sun.
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It tells the story of Earth's first contact with an alien civilisation, the Trisolarans, whose planet is stuck in climatic chaos as it oscillates wildly between the three stars in its stellar system.
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Eta Carinae is the most luminous and massive stellar system with 10,20103 light-years, and is best known for an enormous eruption in the 1840s that hurled at least 10 times the sun's mass into space, leaving an expanding veil of gas and dust.
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The Phi Persei stellar system is located about 716 light-years from Earth.
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If there is no follow-on mechanism, migration (largely) stops and the stellar system becomes (mostly) stable.
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TOI 732, also known as G 162-44 or LP 729-54 is the primary of the binary stellar system LDS 3977 in the constellation Hydra.
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The Leonard–Merritt mass estimator is a formula for estimating the mass of a spherical stellar system using the apparent (angular) positions and proper motions of its component stars. The distance to the stellar system must also be known. Like the virial theorem, the Leonard–Merritt estimator yields correct results regardless of the degree of velocity anisotropy. Its statistical properties are superior to those of the virial theorem.
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HD 43587 is a stellar system approximately 63 light-years away in the constellation of Orion, visible to the naked eye. The system comprises four individual stars, with two widely separated binaries forming a quadruple system.
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81 Cancri (Pi1 Cancri, π1 Cancri) is a stellar system that lies approximately 66 light-years away. The main component of the system is a close binary, while a brown dwarf binary is located at a wide separation.
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Eta Coronae Borealis (η Coronae Borealis, η CrB) is a stellar system that lies approximately 58 light-years away. The primary component is a mid-wide binary, while a brown dwarf component is located at a wide separation.
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In particular, dust and grains can spiral into the star or escape the stellar system under the action of radiation pressure.Comet Hale–Bopp (C/1995 O1). Radiation pressure and solar wind effects on the dust and gas tails are clearly seen.
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It has been suggested that it has a triple stellar system. One of them, which is more massive than other two A-type main-sequence stars, evolved rapidly and became a red giant, swallowing the other two stars, and produced the planetary nebula.
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Of Local Origin New York Times 9 May 1951: 40. Darryl F. Zanuck later said the studio had developed Peters "for seven years" and she "comes through big" in the film.Drama: Old Stellar System Passe, Says Zanuck Los Angeles Times 11 June 1951: B8.
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Exocomets are suggested as one source of white dwarf pollution. After a star from the main sequence becomes a giant star, it loses mass. Planetesimals in an analog of the solar Oort Cloud can be directed toward the inner stellar system. This is a consequence of the mass-loss during the AGB stage.
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Einasto profiles. The Einasto profile (or Einasto model) is a mathematical function that describes how the density \rho of a spherical stellar system varies with distance r from its center. Jaan Einasto introduced his model at a 1963 conference in Alma-Ata, Kazakhstan.J. Einasto (1965), Kinematics and dynamics of stellar systems, Trudy Inst. Astrofiz.
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In 2006, astronomer Margaret Turnbull labeled Beta CVn as the top stellar system candidate to search for extraterrestrial life forms. Because of its solar-type properties, astrobiologists have listed it among the most astrobiologically interesting stars within 10 parsecs of the Sun. However, as of 2009, this star is not known to host planets.
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The Eta Carinids are a meteor shower lasting from January 14 to 27 each year, peaking on January 21. C. S. Nilsson of the Adelaide Observatory discovered them in 1961 in Australia. Roughly two to three meteors occur per hour at its maximum. It gets its name from the radiant which is close to the stellar system Eta Carinae.
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Ritchie commented that "The classic game of inter-stellar system warfare. [...] After five years and three printings, the game remains almost as fresh and exciting as the day it was published. Somewhat complex and long, but can be completed in an afternoon." Tony Watson reviewed the Avalon Hill version of Stellar Conquest in Space Gamer No. 76.
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As stars move through an arm, the space velocity of each stellar system is modified by the gravitational force of the local higher density. Also the newly created stars do not remain forever fixed in the position within the spiral arms, where the average space velocity returns to normal after the stars depart on the other side of the arm.
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1 Hillside Crescent, Edinburgh Thomas Henderson FRSE FRS FRAS (28 December 1798 - 23 November 1844) was a Scottish astronomer and mathematician noted for being the first person to measure the distance to Alpha Centauri, the major component of the nearest stellar system to Earth, the first to determine the parallax of a fixed star, and for being the first Astronomer Royal for Scotland.
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The exoplanet was discovered by transit and is a Hot Jupiter planet orbiting a star in a triple star system, KELT-4. It is the fourth planet found in such a system. As KELT-4A is the brightest host (V~10) of a Hot Jupiter in a hierarchical triple stellar system found so far researchers expect it may be useful in learning more about inflated planets.
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Scholz's Star (WISE designation WISE 0720−0846 or fully WISE J072003.20−084651.2) is a dim binary stellar system from the Sun in the constellation Monoceros near the galactic plane. It was discovered in 2013 by astronomer Ralf-Dieter Scholz. In 2015, Eric Mamajek and collaborators reported the system passed through the Solar System's Oort cloud roughly 70,000 years ago, and dubbed it Scholz's Star.
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The lack of a coma limits the amount of surface ice to a few square meters, and any volatiles (if they exist) must lie below a crust at least thick. It also indicates that the object must have formed within the frost line of its parent stellar system or have been in the inner region of that stellar system long enough for all near-surface ice to sublimate, as may be the case with damocloids. It is difficult to say which scenario is more likely due to the chaotic nature of small body dynamics, although if it formed in a similar manner to Solar System objects, its spectrum indicates that the latter scenario is true. Any meteoric activity from Oumuamua would have been expected to occur on 18 October 2017 coming from the constellation Sextans, but no activity was detected by the Canadian Meteor Orbit Radar.
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Ross 128 is a red dwarf in the equatorial zodiac constellation of Virgo, near β Virginis. The apparent magnitude of Ross 128 is 11.13, which is too faint to be seen with the unaided eye. Based upon parallax measurements, the distance of this star from Earth is , making it the twelfth closest stellar system to the Solar System. It was first cataloged in 1926 by American astronomer Frank Elmore Ross.
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The Ring Nebula in Barnard's Galaxy has the official designation of Hubble 1925 III as it was the third (Roman numeral 3) object recorded in Hubble's 1925 paper, N.G.C. 6822, A Remote Stellar System. It includes areas of bright H II emission. In Paul W. Hodge's 1977 paper it was designated Hodge 4. Its appearance is very similar to the filamentary nebula found in the Large Magellanic Cloud (see Meaburn 1981).
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Edwin Hubble, in the paper N.G.C. 6822, A Remote Stellar System, identified 15 variable stars (11 of which were Cepheids) of this galaxy. He also surveyed the galaxy's stars distribution down to magnitude 19.4. He provided spectral characteristics, luminosities and dimensions for the five brightest "diffuse nebulae" (giant H II regions) that included the Bubble Nebula and the Ring Nebula. He also computed the absolute magnitude of the entire galaxy.
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Hoyle and Wickramasinghe further contended that life forms continue to enter the Earth's atmosphere, and may be responsible for epidemic outbreaks, new diseases, and the genetic novelty necessary for macroevolution. In an Origins Symposium presentation on April 7, 2009, physicist Stephen Hawking stated his opinion about what humans may find when venturing into space, such as the possibility of alien life through the theory of panspermia: "Life could spread from planet to planet or from stellar system to stellar system, carried on meteors." Three series of astrobiology experiments have been conducted outside the International Space Station between 2008 and 2015 (EXPOSE) where a wide variety of biomolecules, microorganisms, and their spores were exposed to the solar flux and vacuum of space for about 1.5 years. Some organisms survived in an inactive state for considerable lengths of time, and those samples sheltered by simulated meteorite material provide experimental evidence for the likelihood of the hypothetical scenario of lithopanspermia.
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HD 93205, or V560 Carinae, is a binary stellar system, in the Carina Nebula (NGC 3372) in the constellation Carina. It consists of two massive O-stars that revolve around each other in 6 days. The more massive member of the pair is an O3.5 main sequence star. The spectrum shows some ionised nitrogen and helium emission lines, indicating some mixing of fusion products to the surface and a strong stellar wind.
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They also note that the discoverers of the two planets around NN Serpentis were confronted with multiple suggestions from various official sources and finally chose to use the designations "NN Ser c" and "NN Ser d". The proposal of Hessman et al. starts with the following two rules: :Rule 1. The formal name of an exoplanet is obtained by appending the appropriate suffixes to the formal name of the host star or stellar system.
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14,000 light-years from Earth in a stellar system in the Scorpio Cluster, lies the planet of Boazan. Their social system revolves around oligopolistic politics by the nobles, with a caste system. Those with horns are considered noble and have high status, while the hornless are treated as slaves. But when La Gour is about to ascend to the throne, he was exposed as hornless by his ambitious bastard cousin Zu Zambajil and enslaved by the empire.
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His mother was a mining engineer, who died in a mine accident soon after his birth. Because his father was busy with political activities, Jinto was brought up by his father's secretary, Teal Clint. When the Abh Empire invaded Hyde stellar system, his father surrendered the system in exchange for several concessions including selecting the territorial lord from amongst the people of Martine. As a result, Jinto rose to the ranks of Abh nobility along with his father.
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OGLE-TR-123 is a binary stellar system containing one of the smallest main- sequence stars whose radius has been measured. It was discovered when the Optical Gravitational Lensing Experiment (OGLE) survey observed the smaller star eclipsing the larger primary. The orbital period is approximately 1.80 days. The smaller star, OGLE-TR-123b, is estimated to have a radius around 0.13 solar radii, and a mass of around 0.085 solar masses (), or approximately 90 times Jupiter's.
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Richey received their undergraduate degree in Physics at Wheeling Jesuit University in 2004. They completed their Masters (2007) and PhD (2011) in Physics from the University of Alabama at Birmingham, where they did laboratory investigations related to both the icy moons of the outer solar system and the interstellar medium. They were a NASA postdoctoral fellow at NASA Goddard Space Flight Center, where they studied the optical properties of dust grain analogs to better understand early stellar system formation.
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The Homunculus Nebula is a bipolar emission and reflection nebula surrounding the massive star system Eta Carinae, about () from Earth. The nebula is embedded within the much larger Carina Nebula, a large star-forming H II region. From the Latin homunculus meaning Little Man, the nebula consists of gas which was ejected from Eta Carinae in 1841. It also contains dust which absorbs much of the light from the extremely luminous central stellar system and re-radiates it as infra-red (IR).
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Mira (), designation Omicron Ceti (ο Ceti, abbreviated Omicron Cet, ο Cet), is a red giant star estimated to be 200–400 light-years from the Sun in the constellation Cetus. ο Ceti is a binary stellar system, consisting of a variable red giant (Mira A) along with a white dwarf companion (Mira B). Mira A is a pulsating variable star and was the first non-supernova variable star discovered, with the possible exception of Algol. It is the prototype of the Mira variables.
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Earth's hydrosphere. Water covers 71% of Earth's surface, with the global ocean accounting for 97.3% of the water distribution on Earth. A planet cannot have a hydrosphere—a key ingredient for the formation of carbon-based life—unless there is a source for water within its stellar system. The origin of water on Earth is still not completely understood; possible sources include the result of impacts with icy bodies, outgassing, mineralization, leakage from hydrous minerals from the lithosphere, and photolysis.
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Tholins might have also been detected in the stellar system of the young star HR 4796A using the Near-Infrared Camera and Multi-Object Spectrometer (NICMOS) aboard the Hubble Space Telescope. The HR 4796 system is approximately 220 light years from Earth. Models show that even when far from UV radiation of a star, cosmic ray doses may be fully sufficient to convert carbon-containing ice grains entirely to complex organics in less than the lifetime of the typical interstellar cloud.
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PSR B1257+12 b, alternatively designated PSR B1257+12 A, also named Draugr, is an extrasolar planet approximately 2,300 light-years away in the constellation of Virgo. The planet is the innermost object orbiting the pulsar PSR B1257+12, making it a pulsar planet in the dead stellar system. It is about twice as massive as the Moon, and is listed as the least massive planet (with the mass accurately determined) known, including among the planets in the Solar System.
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Knut Emil Lundmark, born 14 June 1889 in Älvsbyn, Sweden, died 23 April 1958 in Lund, Sweden, was a Swedish astronomer, professor of astronomy and head of the observatory at Lund University from 1929 to 1955. Lundmark received his astronomical education at the observatory of Uppsala University. His dissertation (1920) was titled: The relations of the globular clusters and spiral nebulae to the stellar system. During the 1920s he worked at several observatories in the USA, mainly the Lick Observatory and the Mount Wilson Observatory.
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In 1947 Ambartsumian discovered stellar associations, a new type of stellar system, which led to the conclusion that star formation continues to take place in the Milky Way galaxy. At the time the "idea of star formation as an ongoing process was regarded as very speculative." His discovery was announced in a short publication by the Armenian Academy Sciences. Ambartsumian's discovery was based on his observation of stars of O and B spectral types and T Tauri and flare stars that cluster very loosely.
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HD 206267A is a hierarchical triple star system in the northern circumpolar constellation of Cepheus. Two of the members form a spectroscopic binary that orbit each other with a period of 3.7 days, while a third member lies further away—it is unclear whether this third member is gravitationally bound to the pair. The system is emitting a stellar wind that reaches an exceptional velocity of 3,225 km/s, among the highest measured for stars of this type. This stellar system lies in the nebula IC 1396.
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Fomalhaut, K-type main-sequence star TW Piscis Austrini, and M-type, red dwarf star LP 876-10 constitute a triple system, even though the companions are separated by approximately 8 degrees. Fomalhaut was the first stellar system with an extrasolar planet candidate (designated Fomalhaut b, later named Dagon) imaged at visible wavelengths. Analysis of existing and new data suggests Fomalhaut b is not a planet, rather an expanding dust disk resulting from a former collision. The image was published in Science in November 2008.
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Eta Carinae, surrounded by the Homunculus Nebula Within the large bright nebula is a much smaller feature, immediately surrounding Eta Carinae itself, known as the Homunculus Nebula (from Latin meaning Little Man). It is believed to have been ejected in an enormous outburst in 1841 which briefly made Eta Carinae the second-brightest star in the sky. The Homunculus Nebula is a small H II region, with gas shocked into ionised and excited states. It also absorbs much of the light from the extremely luminous central stellar system and re- radiates it as infrared (IR).
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The spiral arms are thought to be areas of high-density matter, or "density waves". As stars move through an arm, the space velocity of each stellar system is modified by the gravitational force of the higher density. (The velocity returns to normal after the stars depart on the other side of the arm.) This effect is akin to a "wave" of slowdowns moving along a highway full of moving cars. The arms are visible because the high density facilitates star formation, and therefore they harbor many bright and young stars.
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Early speckle interferometry showed that the central region of the Homunculus contains four point-like sources, originally designated A1, A2, A3, and A4. The four speckle objects were later referred to as A, B, C, and D. Higher resolution studies showed that only the brightest source A was truly stellar, and the other three were small nebular condensations. The three Weigelt Blobs are visible primarily in light directly reflected from the Eta Carinae stars. The blobs are believed to lie near the equatorial plane of the stellar system, but their origin is unclear.
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Like all estimators based on moments of the Jeans equations, the Leonard–Merritt estimator requires an assumption about the relative distribution of mass and light. As a result, it is most useful when applied to stellar systems that have one of two properties: # All or almost all of the mass resides in a central object, or, # the mass is distributed in the same way as the observed stars. Case (1) applies to the nucleus of a galaxy containing a supermassive black hole. Case (2) applies to a stellar system composed entirely of luminous stars (i.e.
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The young age of the stellar system (about 16 million years) and the high mass of the ring system (roughly an Earth mass) are more consistent with it being an early (proto-)exomoon or moons, rather than a long-term stable ring system in an evolved planetary system (such as Saturn's rings). J1407b has not been observed since its transit in 2007, suggesting that it is on a highly eccentric orbit around the star. Such a highly eccentric orbit around the star could disrupt the ring system of J1407b.
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After two supermassive black holes coalesce, emission of linear momentum can produce a "kick" with amplitude as large as 4000 km/s. This is fast enough to eject the coalesced black hole completely from its host galaxy. Even if the kick is too small to eject the black hole completely, it can remove it temporarily from the nucleus of the galaxy, after which it will oscillate about the center, eventually coming to rest. A kicked black hole can also carry a star cluster with it, forming a hyper-compact stellar system.
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Since the elongation of a stellar system with this anisotropy is approximately 15:1 — much more extreme than observed in real galaxies — bending instabilities were believed for many years to be of little importance. However, Fridman & Polyachenko showed that the critical axis ratio for stability of homogeneous (constant-density) oblate and prolate spheroids was roughly 3:1, not 15:1 as implied by the infinite slab, and Merritt & Hernquist found a similar result in an N-body study of inhomogeneous prolate spheroids (Fig. 1). The discrepancy was resolved in 1994.
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Devoure admits that the Sirians have established a base on Titan, but insists that the fact that Saturn and its moons are part of Earth's stellar system is irrelevant: "An empty world is an empty world, regardless of the particular route it travels through space. We colonized it first and it is ours". Devoure then brings out Starr, who admits to having re-entered the Saturnian system after being warned off, and also that Wessilewsky established a base on Mimas. Conway then receives permission to cross-examine Starr.
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Given the large number of objects in a stellar system, stellar dynamics is usually concerned with the more global, statistical properties of several orbits rather than with the specific data on the positions and velocities of individual orbits. The motions of stars in a galaxy or in a globular cluster are principally determined by the average distribution of the other, distant stars. Stellar encounters involve processes such as relaxation, mass segregation, tidal forces, and dynamical friction that influence the trajectories of the system's members. Stellar dynamics also has connections to the field of plasma physics.
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In generic potentials, some orbits respect only one or two integrals and the corresponding motion is chaotic. Jeans's theorem can be generalized to such potentials as follows: > The phase-space density of a stationary stellar system is constant within > every well-connected region. A well-connected region is one that cannot be decomposed into two finite regions such that all trajectories lie, for all time, in either one or the other. Invariant tori of regular orbits are such regions, but so are the more complex parts of phase space associated with chaotic trajectories.
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Several KOIs contain transiting objects which are hotter than the stars they transit, indicating that the smaller objects are white dwarfs formed through mass transfer. These objects include KOI 74, KOI 81 and KOI 959. KOI 54 is believed to be a binary system containing two Class-A stars in highly eccentric orbits with a semi-major axis of 0.4 AU. During periastron, tidal distortions cause a periodic brightening of the system. In addition, these tidal forces induce resonant pulsations in one (or both) of the stars, making it only the 4th known stellar system to exhibit such behavior.
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A hypercompact stellar system (HCSS) is a dense cluster of stars around a supermassive black hole that has been ejected from the center of its host galaxy. Stars that are close to the black hole at the time of the ejection will remain bound to the black hole after it leaves the galaxy, forming the HCSS. The term "hypercompact" refers to the fact HCSSs are small in size compared with ordinary star clusters of similar luminosity. This is because the gravitational force from the supermassive black hole keeps the stars moving in very tight orbits about the center of the cluster.
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Loïc got along well and was respected by her subordinates, though she had some hesitance in contacting Lafiel on non- military matters due to her high noble rank, preferring to go through Jinto instead, and was a highly able commander. ; Abriel Nei Debrusc Spunej Ramaj : The current reigning empress of the Abh Empire, she is also Lafiel's grandmother. She also holds the title "Dreuc Ablïarser" (Countess of Ablïarsec; Ablïarsec is also the name of the stellar system where Lakfakalle (Lacmhacarh), the imperial capital, is located). All interstellar ships belong to the crown which are then leased out to the merchants of the empire.
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Stellar dynamics is the branch of astrophysics which describes in a statistical way the collective motions of stars subject to their mutual gravity. The essential difference from celestial mechanics is that each star contributes more or less equally to the total gravitational field, whereas in celestial mechanics the pull of a massive body dominates any satellite orbits. Historically, the methods utilized in stellar dynamics originated from the fields of both classical mechanics and statistical mechanics. In essence, the fundamental problem of stellar dynamics is the N-body problem, where the N members refer to the members of a given stellar system.
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The first well recorded observation of the star system using optical instruments was made by James Bradley on 25 September 1753, when he noticed that it was a double star. William Herschel began systematic observations of 61 Cygni as part of a wider study of binary stars. His observations led to the conclusion that binary stars were separated enough that they would show different movements in parallax over the year, and hoped to use this as a way to measure the distance to the stars. alt=GIF showing the proper motion of the stellar system, taken about in an interval of an year.
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Among all stars or stellar systems listed in the modern Hipparcos Catalogue, 61 Cygni has the seventh-highest proper motion, and the highest among all visible stars or systems.By convention, limiting visual magnitude of 6.0Hipparcos: Catalogues: The Millennium Star Atlas: The Top 20 High Proper Motion, European Space Agency, retrieved 2019-06-27 Over the course of the twentieth century, several different astronomers reported evidence of a massive planet orbiting one of the two stars, but recent high-precision radial velocity observations have shown that all such claims were unfounded. No planets have been confirmed in this stellar system to date.
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This ring system is attributed a radius of about 90 million km (about 200 times that of Saturn's rings). In press releases, the term "super- Saturn" was used. However, the age of this stellar system is only about 16 million years, which suggests that this structure, if real, is more likely a circumplanetary disk rather than a stable ring system in an evolved planetary system. The ring was observed to have a 0.0267 AU-wide gap at a radial distance of 0.4 AU. Simulations suggest that this gap is more likely the result of an embedded moon than resonance effects of an external moon(s).
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Artist's impression of the SCR 1845-6357 stellar system The primary, SCR 1845−6357A, is a faint (apparent magnitude 17.4) ultra-cool red dwarf with a mass of about 7% of the Sun's. However, the measurements are still preliminary and are subject to change. SCR 1845-6357, right bottom This star has been found to possess a brown dwarf companion, designated SCR 1845-6357B. The companion, classified as a T-dwarf, has an observed projected distance of 4.1 AU, an estimated mass between 40 and 50 times the mass of Jupiter, and an estimated effective temperature of 950 K. The brown dwarf has a near-IR J-band magnitude of 13.26.
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Radial velocity measurements of the seen inner component Aa analysed in 2020 indicate that it has a massive unseen companion Ab, which is very likely to be a black hole. Being distant from the Sun, this would make it the closest known black hole to the Sun. As the host stellar system has an apparent magnitude of 5.36, similar to the maximum brightness of planet Uranus, the black hole is the first discovered in one of the 9,000 stellar systems visible to the naked eye. The black hole is not detected in the spectrum and no x-rays have been observed, so any accretion disk around it would have to be a very weak one.
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The Multisystem is a huge artificial stellar system presided over by a Charonian Dyson Sphere where Earth was taken after the Big Jump. It is host to at least eight G-class stars and dozens of Earth-like planets, all stolen from their respective solar systems in the same manner as the Earth and carefully held in their orbits with artificial gravity. The planets are shepherded by a large number of Charonian COREs which destroy any potential threat to the life-bearing planets through direct physical impact, including human spacecraft. NaPurHab: The Naked Purple Habitat, owned and operated by the radical Naked Purple social movement, was brought along in the Big Jump and managed to survive the transition by orbiting around the Moonpoint black hole.
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WASP-120 is a yellow-white main-sequence star around 1.4 times as massive as the Sun with a spectral type of F5V that is estimated to be 2.6 (±0.5) billion years old. It has a massive planet around 4.85 times the mass of Jupiter that completes its orbit every 3.6 days, and has an estimated surface temperature of 1,880 (±70)K. With an apparent magnitude of 13.06, Gliese 1061 is a red dwarf of spectral type M5.5V that has 12% of the mass and 15% of the diameter of the Sun, and shines with only 0.17% of its luminosity. Located 12 light- years away from Earth, it is the 20th-closest single star or stellar system to the Sun.
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Early computer-generated models of planetary formation predicted the existence of terrestrial planets around both Alpha Centauri A and B,See Lissauer and Quintana in references below. but most recent numerical investigations have shown that the gravitational pull of the companion star renders the accretion of planets difficult. Despite these difficulties, given the similarities to the Sun in spectral types, star type, age and probable stability of the orbits, it has been suggested that this stellar system could hold one of the best possibilities for harbouring extraterrestrial life on a potential planet. In the Solar System, Jupiter and Saturn were probably crucial in perturbing comets into the inner Solar System, providing the inner planets with a source of water and various other ices.
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Eta Carinae (η Carinae, abbreviated to η Car), formerly known as Eta Argus, is a stellar system containing at least two stars with a combined luminosity greater than five million times that of the Sun, located around 7,500 light- years (2,300 parsecs) distant in the constellation Carina. Previously a 4th- magnitude star, it brightened in 1837 to become brighter than Rigel, marking the start of its so-called "Great Eruption". It became the second-brightest star in the sky between 11 and 14 March 1843 before fading well below naked eye visibility after 1856. In a smaller eruption, it reached 6th magnitude in 1892 before fading again. It has brightened consistently since about 1940, becoming brighter than magnitude 4.5 by 2014.
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He wrote: "It seems to be a natural consequence of our points of view to assume that the whole of space is filled with electrons and flying electric ions of all kinds. We have assumed that each stellar system in evolutions throws off electric corpuscles into space. It does not seem unreasonable therefore to think that the greater part of the material masses in the universe is found, not in the solar systems or nebulae, but in 'empty' space." In 1916, Birkeland was probably the first person to successfully predict that the solar wind behaves as do all charged particles in an electric field: "From a physical point of view it is most probable that solar rays are neither exclusively negative nor positive rays, but of both kinds".
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Six weeks after returning from the Jovian system, David "Lucky" Starr learns that Jack Dorrance, the chief of a Sirian spy ring uncovered by Starr in the Jovian system, has escaped from Earth. Starr and his sidekick Bigman Jones follow Dorrance to the Saturnian system, where Dorrance tries to lose them in Saturn's rings, but his ship is destroyed by a ring fragment. A Sirian ship then contacts Starr and informs him that the Sirians have built a colony on Titan and claimed it for Sirius, contrary to the traditional principle that inhabitants of one world in a stellar system have sovereignty over the entire system, even those parts without permanent settlements. Starr orders the pursuing Terrestrial fleet back to Earth; but returns with Bigman and Councilman Ben Wessilewsky to the Saturnian system.
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The constraints adopted have definite implications on the stories told. An Earthman may fall in love with and wed an alien princess like Burroughs' John Carter of Mars does, but unlike Carter will never be able to found a dynasty. Nor will he be able to flit from Earth to the stars and back; an interstellar voyage takes months of subjective time and many years in objective time - as dictated by the time dilation of the Theory of relativity - rendering any decision to leave his own stellar system a difficult one, fraught with the consequences of being cut off from his friends, family and native culture for decades, during which they will age or develop much more than he will himself. De Camp somewhat mitigates the problem by postulating the development of longevity treatments that extend human lifespans to two centuries.
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It has been speculated that the object may have been ejected from a stellar system in one of the local kinematic associations of young stars (specifically, Carina or Columba) within a range of about 100 parsecs, some 45 million years ago. The Carina and Columba associations are now very far in the sky from the Lyra constellation, the direction from which Oumuamua came when it entered the Solar System. Others have speculated that it was ejected from a white dwarf system and that its volatiles were lost when its parent star became a red giant. About 1.3 million years ago the object may have passed within a distance of to the nearby star TYC 4742-1027-1, but its velocity is too high to have originated from that star system, and it probably just passed through the system's Oort cloud at a relative speed of about .
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Set in the future, players control members of the Tenno, a race of ancient warriors who have awoken from a century-long cryosleep as they return from a stellar system known as the Tau system after being driven back centuries ago in an ancient war. In the Solar system, they find themselves at war with the Grineer, a matriarchal race of militarized and deteriorated human clones built upon metal, blood, and war; the Corpus, a mega-corporation with advanced robotics and laser technology built upon profit; the Infested, disfigured victims of the Technocyte virus; and the Sentients, a race of self-replicating machines made by a long-dead transhuman race known as the Orokin. The Lotus guides the Tenno through difficult situations, as well as gives hints which help the player defeat enemies. To fight back, the Tenno use bio-mechanical suits, the eponymous Warframes, to channel their unique abilities.
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W75N(B)-VLA2 in 1996 (top) and in 2014 W75N(B)-VLA2 is a massive protostar located in the Cygnus X region some 4,200 light-years from Earth, about 8 times more massivephys.org: VLA images 18 years apart show dramatic difference in young stellar system, 2 April 2015 and 300 times brighter than our Sun, observed in 1996 and 2014 by the Karl G. Jansky Very Large Array (VLA). In 2014 its stellar wind had changed from a compact spherical form to a larger thermal, ionized elliptical one outlining collimated motion, giving critical insight into the very early stages of the formation of a massive star.BBC News: Star's birth glimpsed 'in real time', 3 April 2015 Being able to observe its rapid growth as it happens (in real time in an astronomical context) is unique, according to Huib van Langevelde of Leiden University, one of the authors of a study of the object.
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They are the natural enemies of Wookiees, and both Wookiees and Trandoshans keep each other's dried skins and pelts as prizes. As of the original Star Wars races book, their world of origin (Trandoshan or Dosha) occupies the same stellar system as Kashyyyk (the Wookiee homeworld), and it is this proximity that is the source of much of their enmity for the Wookiee race. Unconfirmed speculation suggests that the short-lived Trandoshani overcame their natural limitations as tool users and their harsh homeworld environment to achieve limited space flight on their own, only to discover that the only other inhabited world in their system was a lush, verdant, prey-rich paradise filled with long-lived and technologically unsophisticated savages, and that they've never quite gotten over their pique. Trandoshan religion consists mainly of trying to score enough Jagannath points (The name appears to derive from Jagannath, a deity from Vaishnavism), earned through bounty-hunting or slavery-based kills, to appease the main goddess, or Scorekeeper.
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With a surface temperature of between 1700 and 2000 K, it is cool enough for clouds to form. Variations in its brightness in visible and infrared spectra suggest it has some form of atmospheric cloud cover. HD 96167 is a star 1.31 ± 0.09 times as massive as the Sun, that has most likely exhausted its core hydrogen and begun expanding and cooling into a yellow subgiant with a diameter 1.86 ± 0.07 times that of the Sun, and 3.4 ± 0.2 times its luminosity. Analysis of its radial velocity revealed it has a planet with a minimum mass 68% that of Jupiter, which takes 498.9 ± 1.0 days to complete an orbit. With the orbital separation varying between 0.38 and 2.22 astronomical units, the orbit is highly eccentric. The stellar system is 279 ± 1 light-years away from the Sun. HD 98649 is a yellow main sequence star, classified as a G4V, that has the same mass and diameter as the Sun, but has only 86% of its luminosity. In 2012, a long-period ( 4951 days) planet companion, at least 6.8 times as massive as Jupiter, was discovered by radial velocity method.
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