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HD 51418
HD 51418 (NY Aurigae) is an Ap star and an α2 CVn variable located about away in the northern constellation of Auriga. With an apparent magnitude of 6.67 and a spectral type of A0, it can be faintly visible by the naked eye as a whitish dot under very good circumstances. The star has been noted as an "extreme lanthanide star," with an overabundance of metals including europium, dysprosium, and holmium, which can be observed in the star's spectra as emission lines. HD 51418 also possesses a strong magnetic field, which fluctuates in strength between . The magnetic minimum is known to occur concurrently with the minimums in luminosity and rare-earth detection. Visual companion Speckle imaging observations conducted in 2009 revealed a previously unresolved companion star at a separation of 0.15 arcseconds. The secondary star, component "B" of the double star WDS 06593+4219 as designated in the Washington Double Star Catalog, is an F-type star An F-type main-sequenc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Auriga
AURIGA (''Antenna Ultracriogenica Risonante per l'Indagine Gravitazionale Astronomica'') is an ultracryogenic resonant bar gravitational wave detector in Italy. It is at the Laboratori Nazionali di Legnaro of the Istituto Nazionale di Fisica Nucleare, near Padova. It is being used for research into gravitational waves and quantum gravity. When the oscillator gets hit with a burst of gravitational waves, it will excite the oscillator and it will vibrate for a time span longer than the duration of the gravitational wave burst. This allows for the extraction of the signal from the detector. See also * LIGO * Weber bar References Astronomical observatories in Italy Gravitational-wave telescopes {{observatory-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Speckle Imaging
Speckle imaging describes a range of high-resolution astronomical imaging techniques based on the analysis of large numbers of short exposures that freeze the variation of atmospheric turbulence. They can be divided into the shift-and-add ("''image stacking''") method and the speckle interferometry methods. These techniques can dramatically increase the resolution of ground-based telescopes, but are limited to bright targets. Explanation The principle of all the techniques is to take very short exposure images of astronomical targets, and then process those so as to remove the effects of astronomical seeing. Use of these techniques led to a number of discoveries, including thousands of binary stars that would otherwise appear as a single star to a visual observer working with a similar-sized telescope, and the first images of sunspot-like phenomena on other stars. Many of the techniques remain in wide use today, notably when imaging relatively bright targets. The resolut ... [...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, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hipparcos Objects
''Hipparcos'' was a scientific satellite of the European Space Agency (ESA), launched in 1989 and operated until 1993. It was the first space experiment devoted to precision astrometry, the accurate measurement of the positions of celestial objects on the sky. This permitted the first high-precision measurements of the intrinsic brightnesses (compared to the less precise apparent brightness), proper motions, and parallaxes of stars, enabling better calculations of their distance and tangential velocity. When combined with radial velocity measurements from spectroscopy, astrophysicists were able to finally measure all six quantities needed to determine the motion of stars. The resulting ''Hipparcos Catalogue'', a high-precision catalogue of more than 118,200 stars, was published in 1997. The lower-precision ''Tycho Catalogue'' of more than a million stars was published at the same time, while the enhanced Tycho-2 Catalogue of 2.5 million stars was published in 2000. ''Hipp ... [...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 to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpha2 Canum Venaticorum Variables
An Alpha2 Canum Venaticorum variable (or α2 CVn variable) is a type of variable star. These stars are chemically peculiar main sequence stars of spectral class B8p to A7p. They have strong magnetic fields and strong silicon, strontium, or chromium spectral lines. Their brightness typically varies by 0.01 to 0.1 magnitudes over the course of 0.5 to 160 days. In addition to their intensities, the intensities and profiles of the spectral lines of α2 CVn variables also vary, as do their magnetic fields. The periods of these variations are all equal and are believed to equal the period of rotation of the star. It is thought that they are caused by an inhomogeneous distribution of metals in the atmospheres of these stars, so that the surface of the star varies in brightness from point to point. The type-star which this class is named after is α² Canum Venaticorum, a star in the binary system of Cor Caroli, which is in the northern constellation of Canes Venatici Canes Ven ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
VizieR
A vizier (; ar, وزير, wazīr; fa, وزیر, vazīr), or wazir, is a high-ranking political advisor or minister in the near east. The Abbasid caliphs gave the title ''wazir'' to a minister formerly called '' katib'' (secretary), who was at first merely a helper but afterwards became the representative and successor of the ''dapir'' (official scribe or secretary) of the Sassanian kings. In modern usage, the term has been used for government ministers in much of the Middle East and beyond. Several alternative spellings are used in English, such as ''vizir'', ''wazir'', and ''vezir''. Etymology Vizier is suggested to be an Iranian word, from the Pahlavi root of ''vičir'', which originally had the meaning of a ''decree'', ''mandate'', and ''command'', but later as its use in Dinkard also suggests, came to mean ''judge'' or ''magistrate''. Arthur Jeffery considers the word to be a "good Iranian" word, as has a well-established root in Avestan language. The Pahlavi ''vič ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GY Andromedae
GY Andromedae (GY And) is an α2 Canum Venaticorum type variable star in the northern constellation Andromeda. Its brightness fluctuates in visual magnitude between 6.27m and 6.41m, making it a challenge to view with the naked eye even in good seeing conditions. The magnetic activity on this star shows an unusually long period of variability, cycling about once every 23 years. Based upon parallax measurements, this star is located at a distance of about from the Earth. This is classified as an Ap/Bp star, with a peculiar spectrum showing lines of chromium and europium that change in intensity over a period matching the variability cycle, although opposite in phase. Its most striking characteristic is the presence of the unstable element promethium in its emission spectrum. All isotopes of this element are radioactive with half lives of 17.7 years or less. The promethium in the outer envelope may be generated by the spontaneous fission of higher mass transuranic eleme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
F-type Star
An F-type main-sequence star (F V) is a main-sequence, hydrogen-fusing star of spectral type F and luminosity class V. These stars have from 1.0 to 1.4 times the mass of the Sun and surface temperatures between 6,000 and 7,600 K.Tables VII and VIII. This temperature range gives the F-type stars a whitish hue when observed by the atmosphere. Because a main-sequence star is referred to as a dwarf star, this class of star may also be termed a yellow-white dwarf (not to be confused with white dwarfs, remnant stars that are a possible final stage of stellar evolution). Notable examples include Procyon A, Gamma Virginis A and B, and KIC 8462852. Spectral standard stars The revised Yerkes Atlas system (Johnson & Morgan 1953) listed a dense grid of F-type dwarf spectral standard stars; however, not all of these have survived to this day as stable standards. The ''anchor points'' of the MK spectral classification system among the F-type main-sequence dwarf stars, i.e. those stan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Washington Double Star Catalog
The Washington Double Star Catalog, or WDS, is a catalog of double stars, maintained at the United States Naval Observatory. The catalog contains positions, magnitudes, proper motions and spectral types and has entries for (as of June 2017) 141,743 pairs of double stars. The catalog also includes multiple stars. In general, a multiple star with ''n'' components will be represented by entries in the catalog for ''n-1'' pairs of stars. History The database used to construct the WDS originated at Lick Observatory, where it was used to construct the Index Catalog of Visual Double Stars, published in 1963. In 1965, under the initiative of Charles Worley, it was transferred to the Naval Observatory. The catalog has since been augmented by many measurements, mainly from the Hipparcos and Tycho catalogues and results from speckle interferometry, as well as other sources. A unique 1–3 letter discovery code is used to identify the observer who reported the information. For example, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
