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Spectroscopic Binary Catalogue
The catalogue of spectroscopic binary orbits (SB) is a compilation of orbital data for spectroscopic binary stars which have been produced since 1969 by Alan Henry Batten of the Dominion Astrophysical Observatory and various collaborators. At the 24th International Astronomical Union general assembly, in 2000, a working group was established to take responsibility for maintenance of the catalogue, and to take it from a paper based system to an online database.IAU official websitIntroductionto SB9 version of the catalogue. 16 October 2003 The 9th catalogue was published in 2004. As of 7 August 2009, the catalogue database contained information on over 2940 binary systems, increasing to 3722 in March 2019. The main components of the current SB9 catalogue, as a work in progress, can be downloaded in gzipped tar ball format. Applications The catalogue is used for a variety of purposes: * Completeness assessments and statistical analysis * Generation of H–R diagrams and definitio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Binary Star
A binary star or binary star system is a system of two stars that are gravitationally bound to and in orbit around each other. Binary stars in the night sky that are seen as a single object to the naked eye are often resolved as separate stars using a telescope, in which case they are called ''visual binaries''. Many visual binaries have long orbital periods of several centuries or millennia and therefore have orbits which are uncertain or poorly known. They may also be detected by indirect techniques, such as spectroscopy (''spectroscopic binaries'') or astrometry (''astrometric binaries''). If a binary star happens to orbit in a plane along our line of sight, its components will eclipse and transit each other; these pairs are called ''eclipsing binaries'', or, together with other binaries that change brightness as they orbit, ''photometric binaries''. If components in binary star systems are close enough, they can gravitationally distort each other's outer stellar atmospheres. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alan Henry Batten
Alan may refer to: People *Alan (surname), an English and Kurdish surname *Alan (given name), an English given name ** List of people with given name Alan ''Following are people commonly referred to solely by "Alan" or by a homonymous name.'' * Alan (Chinese singer) (born 1987), female Chinese singer of Tibetan ethnicity, active in both China and Japan * Alan (Mexican singer) (born 1973), Mexican singer and actor *Alan (wrestler) (born 1975), a.k.a. Gato Eveready, who wrestles in Asistencia Asesoría y Administración * Alan (footballer, born 1979) (Alan Osório da Costa Silva), Brazilian footballer * Alan (footballer, born 1998) (Alan Cardoso de Andrade), Brazilian footballer *Alan I, King of Brittany (died 907), "the Great" * Alan II, Duke of Brittany (c. 900–952) *Alan III, Duke of Brittany(997–1040) *Alan IV, Duke of Brittany (c. 1063–1119), a.k.a. Alan Fergant ("the Younger" in Breton language) * Alan of Tewkesbury, 12th century abbott *Alan of Lynn (c. 1348–1423), 15 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dominion Astrophysical Observatory
The Dominion Astrophysical Observatory, located on Observatory Hill (Saanich), Observatory Hill, in Saanich, British Columbia, was completed in 1918 by the Canadian Government, Canadian government. The Dominion architect responsible for the building was Edgar Lewis Horwood. The main instrument is the Plaskett telescope, proposed and designed by John S. Plaskett in 1910 with the support of the International Union for Cooperation in Solar Research. Following completion, Plaskett remained the head of the observatory until 1935. The observatory has been designated a national historic site of Canada, as it is a world-renowned facility where many discoveries about the nature of the Milky Way were made, and it was one of the world's main Astrophysics, astrophysical research centres until the 1960s. Centre of the Universe The Centre of the Universe is the public interpretive centre for the observatory, located across the parking lot from the Dominion Astrophysical Observatory telescop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astrophysics Data System
The SAO/NASA Astrophysics Data System (ADS) is a digital library portal for researchers on astronomy and physics, operated for NASA by the Smithsonian Astrophysical Observatory. ADS maintains three bibliographic collections containing over 15 million records, including all arXiv e-prints. Abstracts and full-text of major astronomy and physics publications are indexed and searchable through the portal. Historical context Johann Friedrich Weidler published the first comprehensive history of astronomy in 1741 and the first astronomical bibliography in 1755. This was an effort to archive and classify earlier astronomical knowledge and works. This effort was continued by Jérôme de La Lande who published his ''Bibliographie astronomique'' in 1803, a work that covered the period from 480 BCE to the year of publication. The ''Bibliographie générale de l’astronomie, Volume I and Volume II'', published by J.C. Houzeau and A. Lancaster, followed in 1882 until 1889. As the numbe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Astronomical Union
The International Astronomical Union (IAU; , UAI) is an international non-governmental organization (INGO) with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreach, education, and development through global cooperation. It was founded on 28 July 1919 in Brussels, Belgium 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. the Union had 85 national members and 12,734 individual members, spanning 90 countries and territories. 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] |
Orbital Period
The orbital period (also revolution period) is the amount of time a given astronomical object takes to complete one orbit around another object. In astronomy, it usually applies to planets or asteroids orbiting the Sun, moons orbiting planets, exoplanets orbiting other stars, or binary stars. It may also refer to the time it takes a satellite orbiting a planet or moon to complete one orbit. For celestial objects in general, the orbital period is determined by a 360° revolution of one body around its primary, ''e.g.'' Earth around the Sun. Periods in astronomy are expressed in units of time, usually hours, days, or years. Its reciprocal is the orbital frequency, a kind of revolution frequency, in units of hertz. Small body orbiting a central body According to Kepler's Third Law, the orbital period ''T'' of two point masses orbiting each other in a circular or elliptic orbit is: :T = 2\pi\sqrt where: * ''a'' is the orbit's semi-major axis * ''G'' is the gravitationa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orbital Eccentricity
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: * Elliptic orbit: * Parabolic trajectory: * Hyperbolic trajectory: The eccentricity is given by e = \sqrt where ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astronomical Catalogues Of Stars
Astronomy is a natural science that studies astronomical object, celestial objects and the phenomena that occur in the cosmos. It uses mathematics, physics, and chemistry in order to explain their origin and their overall chronology of the Universe, evolution. Objects of interest include planets, natural satellite, moons, stars, nebulae, galaxy, galaxies, meteoroids, asteroids, and comets. Relevant phenomena include supernova explosions, gamma ray bursts, quasars, blazars, pulsars, and cosmic microwave background radiation. More generally, astronomy studies everything that originates beyond atmosphere of Earth, Earth's atmosphere. Cosmology is a branch of astronomy that studies the universe as a whole. Astronomy is one of the oldest natural sciences. The early civilizations in recorded history made methodical observations of the night sky. These include the Egyptian astronomy, Egyptians, Babylonian astronomy, Babylonians, Greek astronomy, Greeks, Indian astronomy, Indians, Ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
