64 relations: Adaptive optics, Akkadian language, Al Achsasi al Mouakket, Angular diameter, Angular distance, Apparent magnitude, Arabic, Asterism (astronomy), Astronomical unit, Babylonian astronomy, Bayer designation, Binary star, Birkhäuser, Boss General Catalogue, Bright Star Catalogue, Cambridge University Press, Catalog of Components of Double and Multiple Stars, Catalogues of Fundamental Stars, Chinese language, Constellation, Coronagraph, CSIRO, Delta Sagittarii, Effective temperature, Eta Sagittarii, Flamsteed designation, Gamma Sagittarii, Gauss (unit), Giant star, Henry Draper Catalogue, Hipparcos, IAU Working Group on Star Names, Index Catalogue of Visual Double Stars, Infrared excess, Interferometry, International Astronomical Union, Lambda Sagittarii, Latin, Latinisation of names, Limb darkening, List of stars in Sagittarius, Main sequence, Minute and second of arc, Monthly Notices of the Royal Astronomical Society, MUL.APIN, Parallax, Phi Sagittarii, Position angle, PPM Star Catalogue, Sagittarius (constellation), ..., Sigma Sagittarii, Smithsonian Astrophysical Observatory Star Catalog, Solar radius, Stellar classification, Stellar evolution, Stellar rotation, Sun, Tau Sagittarii, Warida, Washington Double Star Catalog, Winnowing Basket (Chinese constellation), X-ray astronomy, Zeta Sagittarii, Zodiac. Expand index (14 more) » « Shrink index
Adaptive optics (AO) is a technology used to improve the performance of optical systems by reducing the effect of incoming wavefront distortions by deforming a mirror in order to compensate for the distortion.
Akkadian (akkadû, ak-ka-du-u2; logogram: URIKI)John Huehnergard & Christopher Woods, "Akkadian and Eblaite", The Cambridge Encyclopedia of the World's Ancient Languages.
Muḥammad al-Akhṣāṣī al-Muwaqqit (محمد الاخصاصي الموقت) was an Egyptian astronomer whose calendarium and catalogue of stars, al-Durrah al-muḍīyah fī al-ʻamāl al-shamsīyah ("Pearls of brilliance upon the solar operations"), was written at Cairo about 1650.
The angular diameter, angular size, apparent diameter, or apparent size is an angular measurement describing how large a sphere or circle appears from a given point of view.
In mathematics (in particular geometry and trigonometry) and all natural sciences (e.g. astronomy and geophysics), the angular distance (angular separation, apparent distance, or apparent separation) between two point objects, as viewed from a location different from either of these objects, is the angle of length between the two directions originating from the observer and pointing toward these two objects.
The apparent magnitude of a celestial object is a number that is a measure of its brightness as seen by an observer on Earth.
Arabic (العَرَبِيَّة) or (عَرَبِيّ) or) is a Central Semitic language that first emerged in Iron Age northwestern Arabia and is now the lingua franca of the Arab world. It is named after the Arabs, a term initially used to describe peoples living from Mesopotamia in the east to the Anti-Lebanon mountains in the west, in northwestern Arabia, and in the Sinai peninsula. Arabic is classified as a macrolanguage comprising 30 modern varieties, including its standard form, Modern Standard Arabic, which is derived from Classical Arabic. As the modern written language, Modern Standard Arabic is widely taught in schools and universities, and is used to varying degrees in workplaces, government, and the media. The two formal varieties are grouped together as Literary Arabic (fuṣḥā), which is the official language of 26 states and the liturgical language of Islam. Modern Standard Arabic largely follows the grammatical standards of Classical Arabic and uses much of the same vocabulary. However, it has discarded some grammatical constructions and vocabulary that no longer have any counterpart in the spoken varieties, and has adopted certain new constructions and vocabulary from the spoken varieties. Much of the new vocabulary is used to denote concepts that have arisen in the post-classical era, especially in modern times. During the Middle Ages, Literary Arabic was a major vehicle of culture in Europe, especially in science, mathematics and philosophy. As a result, many European languages have also borrowed many words from it. Arabic influence, mainly in vocabulary, is seen in European languages, mainly Spanish and to a lesser extent Portuguese, Valencian and Catalan, owing to both the proximity of Christian European and Muslim Arab civilizations and 800 years of Arabic culture and language in the Iberian Peninsula, referred to in Arabic as al-Andalus. Sicilian has about 500 Arabic words as result of Sicily being progressively conquered by Arabs from North Africa, from the mid 9th to mid 10th centuries. Many of these words relate to agriculture and related activities (Hull and Ruffino). Balkan languages, including Greek and Bulgarian, have also acquired a significant number of Arabic words through contact with Ottoman Turkish. Arabic has influenced many languages around the globe throughout its history. Some of the most influenced languages are Persian, Turkish, Spanish, Urdu, Kashmiri, Kurdish, Bosnian, Kazakh, Bengali, Hindi, Malay, Maldivian, Indonesian, Pashto, Punjabi, Tagalog, Sindhi, and Hausa, and some languages in parts of Africa. Conversely, Arabic has borrowed words from other languages, including Greek and Persian in medieval times, and contemporary European languages such as English and French in modern times. Classical Arabic is the liturgical language of 1.8 billion Muslims and Modern Standard Arabic is one of six official languages of the United Nations. All varieties of Arabic combined are spoken by perhaps as many as 422 million speakers (native and non-native) in the Arab world, making it the fifth most spoken language in the world. Arabic is written with the Arabic alphabet, which is an abjad script and is written from right to left, although the spoken varieties are sometimes written in ASCII Latin from left to right with no standardized orthography.
In observational astronomy, an asterism is a popular known pattern or group of stars that are recognised in the night sky.
The astronomical unit (symbol: au, ua, or AU) is a unit of length, roughly the distance from Earth to the Sun.
The history of astronomy in Mesopotamia, and the world, begins with the Sumerians who developed the earliest writing system—known as cuneiform—around 3500–3200 BC.
A Bayer designation is a stellar designation in which a specific star is identified by a Greek letter, followed by the genitive form of its parent constellation's Latin name.
A binary star is a star system consisting of two stars orbiting around their common barycenter.
Birkhäuser is a former Swiss publisher founded in 1879 by Emil Birkhäuser.
Boss General Catalogue (GC, sometimes General Catalogue) is an astronomical catalogue containing 33,342 stars.
The Bright Star Catalogue, also known as the Yale Catalogue of Bright Stars or Yale Bright Star Catalogue, is a star catalogue that lists all stars of stellar magnitude 6.5 or brighter, which is roughly every star visible to the naked eye from Earth.
Cambridge University Press (CUP) is the publishing business of the University of Cambridge.
The Catalog of Components of Double and Multiple Stars, or CCDM, is an astrometric star catalogue of double and multiple stars.
The Catalogue of Fundamental Stars is a series of six astrometric catalogues of high precision positional data for a small selection of stars to define a celestial reference frame, which is a standard coordinate system for measuring positions of stars.
Chinese is a group of related, but in many cases mutually unintelligible, language varieties, forming a branch of the Sino-Tibetan language family.
A constellation is a group of stars that are considered to form imaginary outlines or meaningful patterns on the celestial sphere, typically representing animals, mythological people or gods, mythological creatures, or manufactured devices.
A coronagraph is a telescopic attachment designed to block out the direct light from a star so that nearby objects – which otherwise would be hidden in the star's bright glare – can be resolved.
The Commonwealth Scientific and Industrial Research Organisation (CSIRO) is an independent Australian federal government agency responsible for scientific research.
Delta Sagittarii (δ Sagittarii, abbreviated Delta Sgr, δ Sgr), also named Kaus Media, is a double star in the southern zodiac constellation of Sagittarius.
The effective temperature of a body such as a star or planet is the temperature of a black body that would emit the same total amount of electromagnetic radiation.
Eta Sagittarii (Eta Sgr, η Sagittarii, η Sgr) is a binary star system in the southern zodiac constellation of Sagittarius.
A Flamsteed designation is a combination of a number and constellation name that uniquely identifies most naked eye stars in the modern constellations visible from southern England.
The Bayer designation γ Sagittarii (Gamma Sagittarii) is shared by two stars in the constellation Sagittarius.
The gauss, abbreviated as G or Gs, is the cgs unit of measurement of magnetic flux density (or "magnetic induction") (B).
A giant star is a star with substantially larger radius and luminosity than a main-sequence (or dwarf) star of the same surface temperature.
The Henry Draper Catalogue (HD) is an astronomical star catalogue published between 1918 and 1924, giving spectroscopic classifications for 225,300 stars; it was later expanded by the Henry Draper Extension (HDE), published between 1925 and 1936, which gave classifications for 46,850 more stars, and by the Henry Draper Extension Charts (HDEC), published from 1937 to 1949 in the form of charts, which gave classifications for 86,933 more stars.
Hipparcos was a scientific satellite of the European Space Agency (ESA), launched in 1989 and operated until 1993.
The International Astronomical Union (IAU) established a Working Group on Star Names (WGSN) in May 2016 to catalog and standardize proper names for stars for the international astronomical community.
The Index Catalogue of Visual Double Stars, or IDS, is a catalog of double stars.
An infrared excess is a measurement of an astronomical source, typically a star, that in their spectral energy distribution has a greater measured infrared flux than expected by assuming the star is a blackbody radiator.
Interferometry is a family of techniques in which waves, usually electromagnetic waves, are superimposed causing the phenomenon of interference in order to extract information.
The International Astronomical Union (IAU; Union astronomique internationale, UAI) is an international association of professional astronomers, at the PhD level and beyond, active in professional research and education in astronomy.
Lambda Sagittarii (λ Sagittarii, abbreviated Lambda Sgr, λ Sgr), also named Kaus Borealis, is a star within the southern constellation of Sagittarius.
Latin (Latin: lingua latīna) is a classical language belonging to the Italic branch of the Indo-European languages.
Latinisation or Latinization is the practice of rendering a non-Latin name (or word) in a Latin style.
Limb darkening is an optical effect seen in stars (including the Sun), where the center part of the disk appears brighter than the edge or limb of the image.
This is the list of notable stars in the constellation Sagittarius, sorted by decreasing brightness.
In astronomy, the main sequence is a continuous and distinctive band of stars that appear on plots of stellar color versus brightness.
A minute of arc, arcminute (arcmin), arc minute, or minute arc is a unit of angular measurement equal to of one degree.
Monthly Notices of the Royal Astronomical Society (MNRAS) is a peer-reviewed scientific journal covering research in astronomy and astrophysics.
MUL.APIN is the conventional title given to a Babylonian compendium that deals with many diverse aspects of Babylonian astronomy and astrology.
Parallax is a displacement or difference in the apparent position of an object viewed along two different lines of sight, and is measured by the angle or semi-angle of inclination between those two lines.
Phi Sagittarii (Phi Sgr, φ Sagittarii, φ Sgr) is a star in the southern constellation of Sagittarius.
Position angle, usually abbreviated PA, is the convention for measuring angles on the sky in astronomy.
The PPM Star Catalogue (Positions and Proper Motions Star Catalogue) is the successor of the SAO Catalogue.
Sagittarius is one of the constellations of the zodiac.
Sigma Sagittarii (σ Sagittarii, abbreviated Sigma Sgr, σ Sgr), also named Nunki, is the second-brightest star in the constellation of Sagittarius.
The Smithsonian Astrophysical Observatory Star Catalog is an astrometric star catalogue.
Solar radius is a unit of distance used to express the size of stars in astronomy.
In astronomy, stellar classification is the classification of stars based on their spectral characteristics.
Stellar evolution is the process by which a star changes over the course of time.
Stellar rotation is the angular motion of a star about its axis.
The Sun is the star at the center of the Solar System.
Tau Sagittarii (Tau Sgr, τ Sagittarii, τ Sgr) is a star in the southern zodiac constellation of Sagittarius.
Warida or Al Warida is an asterism of the Arabs.
The Washington Double Star Catalog, or WDS, is a catalog of double stars, maintained at the United States Naval Observatory.
The Winnowing Basket mansion (箕宿, pinyin: Jī Xiù) is one of the Twenty-Eight Mansions of the Chinese constellations.
X-ray astronomy is an observational branch of astronomy which deals with the study of X-ray observation and detection from astronomical objects.
Zeta Sagittarii (ζ Sagittarii, abbreviated Zeta Sgr, ζ Sgr) is a triple star system and the third-brightest star in the constellation of Sagittarius.
The zodiac is an area of the sky that extends approximately 8° north or south (as measured in celestial latitude) of the ecliptic, the apparent path of the Sun across the celestial sphere over the course of the year.