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V4046 Sagittarii
V4046 Sagittarii is a young binary consisting of two K-type main-sequence stars. The two stars are about 271 light-years (83 parsecs) away from the Earth. The two stars orbit each other every 2.42 days on a circular orbit. V4046 Sagittarii is surrounded by a massive protoplanetary disk. The disk has a radius of about 370 astronomical units (au) with about 40 Earth masses of dust in the disk. There are two bright inner rings at 14 and 25 au from the center, respectively. V4046 Sagittarii is one of four pre-main-sequence star systems within 100 parsecs with protoplanetary disks, the others being TW Hydrae, HD 141569, and 49 Ceti. The two stars are still accreting matter from the disk, and gas giant planets may be forming in the disk as well. The red dwarf GSC 07396-00759 is separated about 2.82 from V4046 Sagittarii. Since it has a similar motion throughout space with V4046 Sagittarii, GSC 07396-00759 is assumed to be gravitationally bound (although weakly) to V4046 Sag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
V4046SgrLightCurve
V4 or V-4 may refer to: Science and technology * LNER Class V4, a British steam locomotive * V4 engine, a V engine with four cylinders in two banks of two cylinders * Visual area V4, in the visual cortex * Klein four-group, in mathematics * V.4, an ITU-T recommendation for data transmission * ATC code V04 ''Diagnostic agents'', a subgroup of the Anatomical Therapeutic Chemical Classification System * The V4 JavaScript engine for QML * V4, one of six precordial leads in electrocardiography Other uses * Visegrád Group, an alliance of four Central European states - Czech Republic, Hungary, Poland and Slovakia * ''Rheinbote'' or V-4, a German World War II four-stage missile * Saint Kitts & Nevis (ITU prefix) * Vieques Air Link (IATA airline code) * V4, a grade (climbing) In rock climbing, mountaineering, and other climbing disciplines, climbers give a grade to a climbing route or boulder problem, intended to describe concisely the difficulty and danger of climbing it. Different t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HD 141569
HD 141569 is an isolated Herbig Ae/Be star of spectral class A2Ve approximately 364 light-years away in the constellation of Libra. The primary star has two red dwarf companions (orbiting each other) at about nine arcseconds. In 1999, a protoplanetary disk was discovered around the star. A gap in the disk led to speculation about a possible extrasolar planet forming in the disk. In November 2019, researchers studied HD 141569A (pre-main sequence B9.5 star) and made the first polarimetric detection of the inner ring circling the star. This may help better determine essential features of planetary development. According to the researchers, "Considering resolved imaging data from other high-contrast facilities, the HD 1415169A debris disc shapes up to be made of at least three, and potentially four nested rings, with spiral structures on the three spatially resolved rings ..As such, it is an excellent laboratory for studying dynamically perturbed discs." Planetary system ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Objects With Variable Star Designations
Object may refer to: General meanings * Object (philosophy), a thing, being, or concept ** Object (abstract), an object which does not exist at any particular time or place ** Physical object, an identifiable collection of matter * Goal, an aim, target, or objective * Object (grammar), a sentence element, such as a direct object or an indirect object Science, technology, and mathematics Computing * 3D model, a representation of a physical object * Object (computer science), a language mechanism for binding data with methods that operate on that data ** Object-orientation, in which concepts are represented as objects *** Object-oriented programming (OOP), in which an object is an instance of a class or array ** Object (IBM i), the fundamental unit of data storage in the IBM i operating system * Object (image processing), a portion of an image interpreted as a unit * Object file, the output of a compiler or other translator program (also known as "object code") * Object, an in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Henry Draper Catalogue Objects
Henry may refer to: People *Henry (given name) *Henry (surname) * Henry Lau, Canadian singer and musician who performs under the mononym Henry Royalty * Portuguese royalty ** King-Cardinal Henry, King of Portugal ** Henry, Count of Portugal, Henry of Burgundy, Count of Portugal (father of Portugal's first king) ** Prince Henry the Navigator, Infante of Portugal ** Infante Henrique, Duke of Coimbra (born 1949), the sixth in line to Portuguese throne * King of Germany ** Henry the Fowler (876–936), first king of Germany * King of Scots (in name, at least) ** Henry Stuart, Lord Darnley (1545/6–1567), consort of Mary, queen of Scots ** Henry Benedict Stuart, the 'Cardinal Duke of York', brother of Bonnie Prince Charlie, who was hailed by Jacobites as Henry IX * Four kings of Castile: **Henry I of Castile **Henry II of Castile **Henry III of Castile **Henry IV of Castile * Five kings of France, spelt ''Henri'' in Modern French since the Renaissance to italianize the name and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
K-type Main-sequence Stars , an unusual kind of asteroid
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K-type may refer to: *AEC K-type, a bus chassis *K-type star, a stellar spectral classification *K-type filter, a type of electronic filter *K-type asteroid K-type asteroids are relatively uncommon asteroids with a moderately reddish spectrum shortwards of 0.75 μm, and a slight bluish trend longwards of this. They have a low albedo. Their spectrum resembles that of CV and CO meteorites. A larger K t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypothetical Planetary Systems
A hypothesis (plural hypotheses) is a proposed explanation for a phenomenon. For a hypothesis to be a scientific hypothesis, the scientific method requires that one can testable, test it. Scientists generally base scientific hypotheses on previous observations that cannot satisfactorily be explained with the available scientific theories. Even though the words "hypothesis" and "theory" are often used interchangeably, a scientific hypothesis is not the same as a scientific theory. A working hypothesis is a provisionally accepted hypothesis proposed for further research in a process beginning with an educated guess or thought. A different meaning of the term ''hypothesis'' is used in formal logic, to denote the antecedent (logic), antecedent of a proposition; thus in the proposition "If ''P'', then ''Q''", ''P'' denotes the hypothesis (or antecedent); ''Q'' can be called a consequent. ''P'' is the :wikt:assumption, assumption in a (possibly Counterfactual conditional, counterfac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
T Tauri Stars
T Tauri stars (TTS) are a class of variable stars that are less than about ten million years old. This class is named after the prototype, T Tauri, a young star in the Taurus star-forming region. They are found near molecular clouds and identified by their optical variability and strong chromospheric lines. T Tauri stars are pre-main-sequence stars in the process of contracting to the main sequence along the Hayashi track, a luminosity–temperature relationship obeyed by infant stars of less than 3 solar masses () in the pre-main-sequence phase of stellar evolution. It ends when a star of or larger develops a radiative zone, or when a smaller star commences nuclear fusion on the main sequence. History While T Tauri itself was discovered in 1852, the T Tauri class of stars were initially defined by Alfred Harrison Joy in 1945. Characteristics T Tauri stars comprise the youngest visible F, G, K and M spectral type stars (). Their surface temperatures are similar to those o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HD 98800
HD 98800, also catalogued as TV Crateris (TV Crt), is a quadruple star system in the constellation of Crater (the cup). Parallax measurements made by the Hipparcos spacecraft put it at a distance of about 150 light-years (45 parsecs) away, but this value is in high error. The system is located within the TW Hydrae association (TWA), and has received the designation TWA 4. The system consists of HD 98800 A and HD 98800 B each of which contains two stars. In 2007, a debris disk was discovered orbiting HD 98800 B consisting of two rings which indicates there may be an extrasolar planet orbiting within a distance of 1.5 to 2 astronomical units. Stellar system The system is a member of the TW Hydrae association, a group of young stars. Its membership was derived from the fact that its proper motion is similar to other stars in the group. The system itself is estimated to be around 7-10 million years old. HD 98800 is a quadruple system, with two pairs of stars orbi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UX Tauri
UX Tauri, abbreviated as UX Tau, is a binary star system approximately 450 light-years away in the constellation of Taurus (constellation), Taurus (the Bull). It is notable for the fact that, despite its recent (in stellar terms) planetary system#Origin and evolution, creation, the Spitzer Space Telescope discovered that its protoplanetary disk contains a gap. The dust, which normally accumulates in an expanding ring starting right next to the star at such a young age, is either very thin or nonexistent at a range of 0.2 to 56 astronomical unit, AU from the star. Typically, this means that the early ancestors of planets may be forming from the disk, though the star only ignited about 1 million years ago. In contrast, Earth was formed approximately 4.54 billion years ago, placing its formation about sixty million years after the Sun's ignition around 4.6 billion years ago. See also * HD 98800 * Vega * V4046 Sagittarii References External links * * Circumstella ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Red Dwarf
''Red Dwarf'' is a British science fiction comedy franchise created by Rob Grant and Doug Naylor, which primarily consists of a television sitcom that aired on BBC Two between 1988 and 1999, and on Dave since 2009, gaining a cult following. The series follows low-ranking technician Dave Lister, who awakens after being in suspended animation for three million years to find that he is the last living human, and that he is alone on the mining spacecraft ''Red Dwarf''—save for a hologram his deceased bunkmate Arnold Rimmer and "Cat", a life form which evolved from Lister's pregnant cat. As of 2020, the cast includes Chris Barrie as Rimmer, Craig Charles as Lister, Danny John-Jules as Cat, Robert Llewellyn as the sanitation droid Kryten, and Norman Lovett as the ship's computer, Holly. To date, twelve series of the show have aired, (including one miniseries), in addition to a feature-length special ''The Promised Land''. Four novels were published from 1989 to 1996. Two pilot ep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
