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Delta2 Lyrae
Delta2 Lyrae (δ2 Lyr) is a 4th magnitude star in the constellation Lyra (constellation), Lyra, approximately 900 light years away from Earth. It is one of the M4II spectral standard stars, meaning it is a bright giant star with a surface temperature around 3,600 kelvins. It puts out more energy than 10,000 suns, although more than 90% of it at longer than visual wavelengths. Direct angular measurements, combined with the Hipparcos parallax, give a radius of 1.1 - 1.3 astronomical units, comparable to the size calculated from other observed data. It began life as a hot blue main sequence star, but now is a large cool asymptotic giant branch star with a degenerate matter, degenerate carbon-oxygen core. It is a semi-regular variable star that has its brightness change by 0.2 magnitudes over an ill-defined period. Delta2 Lyrae was once thought to form a visual binary with the star Delta1 Lyrae, Delta1 Lyrae, but it does not, only appearing to do so if seen from ear ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lyra (constellation)
Lyra (; Latin for lyre, from Greek ''λύρα'') is a small constellation. It is one of the 48 listed by the 2nd century astronomer Ptolemy, and is one of the modern 88 constellations recognized by the International Astronomical Union. Lyra was often represented on star maps as a vulture or an eagle carrying a lyre, and hence is sometimes referred to as Vultur Cadens or Aquila Cadens ("Falling Vulture" or "Falling Eagle"), respectively. Beginning at the north, Lyra is bordered by Draco, Hercules, Vulpecula, and Cygnus. Lyra is nearly overhead in temperate northern latitudes shortly after midnight at the start of summer. From the equator to about the 40th parallel south it is visible low in the northern sky during the same (thus winter) months. Vega, Lyra's brightest star, is one of the brightest stars in the night sky, and forms a corner of the famed Summer Triangle asterism. Beta Lyrae is the prototype of a class of binary stars known as Beta Lyrae variables. These binary sta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astronomical Unit
The astronomical unit (symbol: au, or or AU) is a unit of length, roughly the distance from Earth to the Sun and approximately equal to or 8.3 light-minutes. The actual distance from Earth to the Sun varies by about 3% as Earth orbits the Sun, from a maximum (aphelion) to a minimum (perihelion) and back again once each year. The astronomical unit was originally conceived as the average of Earth's aphelion and perihelion; however, since 2012 it has been defined as exactly (see below for several conversions). The astronomical unit is used primarily for measuring distances within the Solar System or around other stars. It is also a fundamental component in the definition of another unit of astronomical length, the parsec. History of symbol usage A variety of unit symbols and abbreviations have been in use for the astronomical unit. In a 1976 resolution, the International Astronomical Union (IAU) had used the symbol ''A'' to denote a length equal to the astronomical ... [...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] |
Bright Star Catalogue Objects
Bright may refer to: Common meanings *Bright, an adjective meaning giving off or reflecting illumination; see Brightness *Bright, an adjective meaning someone with intelligence People * Bright (surname) * Bright (given name) *Bright, the stage name of Thai actor/musician Vachirawit Chiva-aree Places Australia * Bright, Victoria, a town * Electoral district of Bright in South Australia Canada * Bright Parish, New Brunswick Northern Ireland *Bright, County Down, a village and parish in County Down United States *Bright, Indiana, a census-designated place * Bright, West Virginia, an unincorporated community * Bright, Wisconsin, an unincorporated community Arts and entertainment Music *Bright (American band), an experimental pop group from Brooklyn, New York ** ''Bright'' (Bright (American band) album), the eponymous debut from the aforementioned group *Bright (Japanese band), a dance vocal band from Japan ** ''Bright'' (Bright (Japanese band) album) * "Bright" (song), a song b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flamsteed Objects
John Flamsteed (19 August 1646 – 31 December 1719) was an English astronomer and the first Astronomer Royal. His main achievements were the preparation of a 3,000-star catalogue, ''Catalogus Britannicus'', and a star atlas called ''Atlas Coelestis'', both published posthumously. He also made the first recorded observations of Uranus, although he mistakenly catalogued it as a star, and he laid the foundation stone for the Royal Greenwich Observatory. Life Flamsteed was born in Denby, Derbyshire, England, the only son of Stephen Flamsteed and his first wife, Mary Spadman. He was educated at the free school of Derby and at Derby School, in St Peter's Churchyard, Derby, near where his father carried on a malting business. At that time, most masters of the school were Puritans. Flamsteed had a solid knowledge of Latin, essential for reading the scientific literature of the day, and a love of history, leaving the school in May 1662.Birks, John L. (1999) ''John Flamsteed, the f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bayer Objects
Bayer AG (, commonly pronounced ; ) is a German multinational pharmaceutical and biotechnology company and one of the largest pharmaceutical companies in the world. Headquartered in Leverkusen, Bayer's areas of business include pharmaceuticals; consumer healthcare products, agricultural chemicals, seeds and biotechnology products. The company is a component of the Euro Stoxx 50 stock market index. Bayer was founded in 1863 in Barmen as a partnership between dye salesman Friedrich Bayer and dyer Friedrich Weskott. As was common in this era, the company was established as a dyestuffs producer. The versatility of aniline chemistry led Bayer to expand their business into other areas, and in 1899 Bayer launched the compound acetylsalicylic acid under the trademarked name Aspirin. In 1904 Bayer received a trademark for the "Bayer Cross" logo, which was subsequently stamped onto each aspirin tablet, creating an iconic product that is still sold by Bayer. Other commonly known produ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Star System
A star system or stellar system is a small number of stars that orbit each other, bound by gravitational attraction. A large group of stars bound by gravitation is generally called a '' star cluster'' or '' galaxy'', although, broadly speaking, they are also star systems. Star systems are not to be confused with planetary systems, which include planets and similar bodies (such as comets). A star system of two stars is known as a '' binary star'', ''binary star system'' or ''physical double star''. If there are no tidal effects, no perturbation from other forces, and no transfer of mass from one star to the other, such a system is stable, and both stars will trace out an elliptical orbit around the barycenter of the system indefinitely. ''(See Two-body problem)''. Examples of binary systems are Sirius, Procyon and Cygnus X-1, the last of which probably consists of a star and a black hole. Multiple star systems A multiple star system consists of three or more stars that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aitken Double Star Catalogue
The Aitken Double Star Catalogue, or ADS, is a star catalogue of double stars. It was compiled by Robert Grant Aitken and published in 1932 in two volumes, under the name ''New general catalogue of double stars within 120° of the North Pole''. It contains measurements of 17,180 double stars north of declination −30°. Entries in this catalogue are generally referred to by an index number prefixed with the letters ''ADS''. The catalog was a successor to the Burnham Double Star Catalogue and was based on observations compiled by Sherburne Wesley Burnham from 1906 to 1912, and by Eric Doolittle from 1912 to 1919. Aitken began work on the catalog shortly after Doolittle's death in 1920. The catalog contains observations made up to 1927. See also * Index Catalogue of Visual Double Stars * 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, ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stephenson 1
{{Citation , last1 = Wu , first1 = Zhen-Yu , last2 = Zhou , first2 = Xu , last3 = Ma , first3 = Jun , last4 = Du , first4 = Cui-Hua , display-authors = 1 , title = The orbits of open clusters in the Galaxy , journal = Monthly Notices of the Royal Astronomical Society , volume = 399 , issue = 4 , pages = 2146–2164 , date=November 2009 , arxiv = 0909.3737 , bibcode = 2009MNRAS.399.2146W , doi = 10.1111/j.1365-2966.2009.15416.x , s2cid = 6066790 , postscript = . {{citation , display-authors=1 , last1=Özdarcan , first1=O. , last2=Sipahi , first2=E. , last3=Dal , first3=H. A. , title=BD+36 3317: An algol type eclipsing binary in Delta Lyrae cluster , journal=New Astronomy , volume=17 , issue=5 , pages=483–487 , date=July 2012 , doi=10.1016/j.newast.2011.12.002 , bibcode=2012NewA...17..483O , postscript=. , arxiv = 1207.0194 , s2cid=118588705 {{citation , display-authors=1 , last1=Piskunov , firs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Open Cluster
An open cluster is a type of star cluster made of up to a few thousand stars that were formed from the same giant molecular cloud and have roughly the same age. More than 1,100 open clusters have been discovered within the Milky Way galaxy, and many more are thought to exist. They are loosely bound by mutual gravity, gravitational attraction and become disrupted by close encounters with other clusters and clouds of gas as they orbit the Galactic Center. This can result in a migration to the main body of the galaxy and a loss of cluster members through internal close encounters. Open clusters generally survive for a few hundred million years, with the most massive ones surviving for a few billion years. In contrast, the more massive globular clusters of stars exert a stronger gravitational attraction on their members, and can survive for longer. Open clusters have been found only in spiral galaxy, spiral and irregular galaxy, irregular galaxies, in which active star formation is o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Delta1 Lyrae
Delta1 Lyrae, its name Latinisation of names, Latinized from δ1 Lyrae, is a binary star system in the northern constellation of Lyra (constellation), Lyra. It is dimly visible to the naked eye at night with a combined apparent visual magnitude of 5.56. The system is located at a distance of approximately 1,160 light years from the Sun based on stellar parallax, parallax, but is drifting closer with a radial velocity of −26 km/s. Olin J. Eggen, O. J. Eggen originally included this as a candidate member of the proposed Delta Lyrae cluster. The variable radial velocity of this star was discovered from photographic plates taken at the Yerkes Observatory in 1904. The first set of orbital elements was computed by Frank Craig Jordan in 1916. It is a single-lined spectroscopic binary with an orbital period of 88.4 days and an orbital eccentricity, eccentricity (ovalness) of 0.37. The visible component of the pair has a blue-white hue with a stellar classificat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Visual Binary
A visual binary is a gravitationally bound binary star system that can be resolved into two stars. These stars are estimated, via Kepler's third law, to have periods ranging from a few years to thousands of years. A visual binary consists of two stars, usually of a different brightness. Because of this, the brighter star is called the primary and the fainter one is called the companion. If the primary is too bright, relative to the companion, this can cause a glare making it difficult to resolve the two components. However, it is possible to resolve the system if observations of the brighter star show it to wobble about a centre of mass. In general, a visual binary can be resolved into two stars with a telescope if their centres are separated by a value greater than or equal to one arcsecond, but with modern professional telescopes, interferometry, or space-based equipment, stars can be resolved at closer distances. For a visual binary system, measurements taken need to specify, in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
