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Psi Draconis
The Bayer designation Psi Draconis (ψ Dra / ψ Draconis) is shared by two star systems, in the constellation Draco Draco is the Latin word for serpent or dragon. Draco or Drako may also refer to: People * Draco (lawgiver) (from Greek: Δράκων; 7th century BC), the first lawgiver of ancient Athens, Greece, from whom the term ''draconian'' is derived * ...: * ψ¹ Draconis * ψ² Draconis {{SIA , astronomical objects Draconis, Psi Draco (constellation) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bayer Designation
A Bayer designation is a stellar designation in which a specific star is identified by a Greek or Latin letter followed by the genitive form of its parent constellation's Latin name. The original list of Bayer designations contained 1,564 stars. The brighter stars were assigned their first systematic names by the German astronomer Johann Bayer in 1603, in his star atlas ''Uranometria''. Bayer catalogued only a few stars too far south to be seen from Germany, but later astronomers (including Nicolas-Louis de Lacaille and Benjamin Apthorp Gould) supplemented Bayer's catalog with entries for southern constellations. Scheme Bayer assigned a lowercase Greek letter (alpha (α), beta (β), gamma (γ), etc.) or a Latin letter (A, b, c, etc.) to each star he catalogued, combined with the Latin name of the star's parent constellation in genitive (possessive) form. The constellation name is frequently abbreviated to a standard three-letter form. For example, Aldebaran in the constellation ... [...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] |
Constellation
A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy), a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object. The origins of the earliest constellations likely go back to prehistory. People used them to relate stories of their beliefs, experiences, creation myth, creation, or mythology. Different cultures and countries adopted their own constellations, some of which lasted into the early 20th century before today's constellations were internationally recognized. The recognition of constellations has changed significantly over time. Many changed in size or shape. Some became popular, only to drop into obscurity. Some were limited to a single culture or nation. The 48 traditional Western constellations are Greek. They are given in Aratus' work ''Phenomena'' and Ptolemy's ''Almagest'', though their origin probably predates these works by several centuries. Constellation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Draco (constellation)
Draco is a constellation in the far northern sky. Its name is Latin for dragon. It was one of the 48 Lists of constellations, constellations listed by the 2nd century astronomer Ptolemy, and remains one of the 88 modern constellations today. The north pole of the ecliptic is in Draco. Draco is circumpolar star, circumpolar from northern latitudes. There it is never setting and therefore can be seen all year. Features Stars Thuban (α Draconis) was the northern pole star from 3942 BC, when it moved farther north than Theta Boötis, until 1793 BC. The Egyptian Pyramids were designed to have one side facing north, with an entrance passage geometrically aligned so that Thuban would be visible at night. Due to the effects of Axial precession (astronomy), precession, it would again be the pole star around the year AD 21000. It is a blue-white giant star of magnitude 3.7, 309 light-years from Earth. The traditional name of Alpha Draconis, Thuban, means "head of the serpent". T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Psi1 Draconis
Psi¹ Draconis (ψ¹ Draconis, abbreviated Psi¹ Dra, ψ¹ Dra), also designated 31 Draconis, is a triple star system in the northern constellation of Draco. The system is fairly close, and is located about 75 light-years (23 parsecs) from the Sun, based on its parallax. Psi¹ Draconis was considered a binary star consisting of an F-type subgiant and an F-type main-sequence star, designated Psi¹ Draconis A (officially named Dziban , from the traditional name of the system) and Psi¹ Draconis B, respectively. In 2015, Psi¹ Draconis A was itself found to be a double-lined spectroscopic binary, making the system a triple. The companion to Psi¹ Draconis A was designated Psi¹ Draconis C by its discoverers. Also in 2015, Psi¹ Draconis B was discovered to be orbited by an exoplanet, designated Psi¹ Draconis Bb. Nomenclature ''ψ¹ Draconis'' ( Latinised to ''Psi¹ Draconis'') is the system's Bayer designation and ''31 Draconis'' its Flamsteed designation. The designati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Psi2 Draconis
Psi2 Draconis is a solitary giant star in the northern circumpolar constellation of Draco, also designated 34 Draconis. It lies just over a degree east of the brighter Psi1 Draconis. Psi2 Draconis has a yellow-white hue and is dimly visible to the naked eye with an apparent visual magnitude of 5.45. It is located at a distance of from the Sun based on parallax, but is drifting closer with a radial velocity of −2 km/s. According to R. O. Gray and associates (2001), the stellar classification of Psi2 Draconis is F2III+; a star that has used up its core hydrogen, cooled, and expanded away from the main sequence. A. P. Cowley and W. P. Bidelman (1979) found a similar class of F3 II-III, with the comment that the spectrum showed "many weak lines". Based on the abundance of iron, the metallicity of this star is much lower than in the Sun. It is about 800 million years old and is spinning with a projected rotational velocity of 50 km/s. The star has dou ... [...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] |
