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δ Cygni
Delta Cygni is a binary star of a combined third-magnitude in the constellation of Cygnus. It is also part of the Northern Cross asterism whose brightest star is Deneb. Its name is a Bayer designation that is Latinized from δ Cygni, and abbreviated Delta Cyg or δ Cyg. Based upon parallax measurements obtained during the Hipparcos mission, Delta Cygni is located roughly distant from the Sun. Delta Cygni's two components are designated Delta Cygni A (officially named Fawaris ) and B. More widely separated is a faint third component, a 12th magnitude star that is moving along with the others. Together they form a triple star system. Nomenclature ''δ Cygni'' ( Latinised to ''Delta Cygni'') is the binary's Bayer designation. The designations of the two components as ''Delta Cygni A'' and ''B'' derive from the convention used by the Washington Multiplicity Catalog (WMC) for multiple star systems, and adopted by the International Astronomical Union (IAU). Traditio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cygnus (constellation)
Cygnus is a northern constellation on the plane of the Milky Way, deriving its name from the Latinisation of names, Latinized Greek language, Greek word for swan. Cygnus is one of the most recognizable constellations of the northern summer and autumn, and it features a prominent asterism (astronomy), asterism known as the Northern Cross (asterism), Northern Cross (in contrast to the Southern Cross). Cygnus was among the 48 constellations listed by the 2nd century astronomer Ptolemy, and it remains one of the 88 modern constellations. Cygnus contains Deneb (ذنب, translit. ''ḏanab,'' tail)one of the brightest stars in the night sky and the most distant first-magnitude staras its "tail star" and one corner of the Summer Triangle the constellation forming an east pointing Altitude (triangle), altitude of the triangle. It also has some notable X-ray sources and the giant stellar association of Cygnus OB2. One of the stars of this association, NML Cygni, is one of the List of larg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gamma Cygni
Gamma Cygni is a star in the northern constellation of Cygnus, forming the intersection of an asterism of five stars called the Northern Cross. It is officially named Sadr , gamma Cygni is its Bayer designation, which that is Latinized from γ Cygni, and abbreviated Gamma Cyg or γ Cyg. Based upon parallax measurements obtained during the Hipparcos mission, it is approximately 1,800 light-years (560 parsecs) from the Sun. It forms the primary or 'A' component of a multiple star system designated WDS J20222+4015 (the secondary or 'BCD' component is WDS J20222+4015BCD, a close triplet of stars 41" away from γ Cygni). Nomenclature ''γ Cygni'' ( Latinised to ''Gamma Cygni'') is the star's Bayer designation. WDS J20222+4015A is its designation in the Washington Double Star Catalog. It bore the traditional name ''Sadr'' (also rendered ''Sadir'' or ''Sador''), derived from the Arabic صدر ''ṣadr'' "chest", the same word which gave rise to the star Schedar ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Luminosity
Luminosity is an absolute measure of radiated electromagnetic radiation, electromagnetic energy per unit time, and is synonymous with the radiant power emitted by a light-emitting object. In astronomy, luminosity is the total amount of electromagnetic energy emitted per unit of time by a star, galaxy, or other astronomical object, astronomical objects. In SI units, luminosity is measured in joules per second, or watts. In astronomy, values for luminosity are often given in the terms of the Solar luminosity, luminosity of the Sun, ''L''⊙. Luminosity can also be given in terms of the astronomical Magnitude (astronomy), magnitude system: the Absolute magnitude#Bolometric magnitude, absolute bolometric magnitude (''M''bol) of an object is a logarithmic measure of its total energy emission rate, while absolute magnitude is a logarithmic measure of the luminosity within some specific wavelength range or Passband, filter band. In contrast, the term ''brightness'' in astronomy is gene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Main-sequence
In astronomy, the main sequence is a classification of stars which appear on plots of stellar color versus brightness as a continuous and distinctive band. Stars on this band are known as main-sequence stars or dwarf stars, and positions of stars on and off the band are believed to indicate their physical properties, as well as their progress through several types of star life-cycles. These are the most numerous true stars in the universe and include the Sun. Color-magnitude plots are known as Hertzsprung–Russell diagrams after Ejnar Hertzsprung and Henry Norris Russell. After condensation and ignition of a star, it generates thermal energy in its dense core region through nuclear fusion of hydrogen into helium. During this stage of the star's lifetime, it is located on the main sequence at a position determined primarily by its mass but also based on its chemical composition and age. The cores of main-sequence stars are in hydrostatic equilibrium, where outward thermal p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spectral Classification
''Spectral'' is a 2016 Hungarian-American military science fiction action film co-written and directed by Nic Mathieu. Written with Ian Fried & George Nolfi, the film stars James Badge Dale as DARPA research scientist Mark Clyne, with Max Martini, Emily Mortimer, Clayne Crawford, and Bruce Greenwood in supporting roles. The film is set in a civil war-ridden Moldova as invisible entities slaughter any living being caught in their path. The film was released worldwide on December 9, 2016 on Netflix. On February 1, 2017, Netflix released a prequel graphic novel of the film called ''Spectral: Ghosts of War'' which was made available digitally through the website ComiXology. Plot DARPA researcher Mark Clyne is sent to a US military airbase on the outskirts of Chișinău, to consult his created line of hyperspectral imaging goggles issued to US Army Special Forces led by Army General James Orland, who is covertly supporting the Moldovan government in an ongoing civi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Giant Star
A giant star has a substantially larger radius and luminosity than a main-sequence (or ''dwarf'') star of the same surface temperature. They lie above the main sequence (luminosity class V in the Yerkes spectral classification) on the Hertzsprung–Russell diagram and correspond to luminosity classes II and III. The terms ''giant'' and ''dwarf'' were coined for stars of quite different luminosity despite similar temperature or spectral type (namely K and M) by Ejnar Hertzsprung in 1905 or 1906. Giant stars have radii up to a few hundred times the Sun and luminosities over 10 times that of the Sun. Stars still more luminous than giants are referred to as supergiants and hypergiants. A hot, luminous main-sequence star may also be referred to as a giant, but any main-sequence star is properly called a dwarf, regardless of how large and luminous it is. Formation A star becomes a giant after all the hydrogen available for fusion at its core has been depleted and, as a r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chinese Star Names
Chinese star names ( Chinese: , ''xīng míng'') are named according to ancient Chinese astronomy and astrology. The sky is divided into star mansions (, ''xīng xiù'', also translated as "lodges") and asterisms (, ''xīng guān''). The ecliptic is divided into four sectors that are associated with the Four Symbols, guardians in Chinese mythology, and further into 28 mansions. Stars around the north celestial pole are grouped into three enclosures (, ''yuán''). The system of 283 asterisms under the Three Enclosures and Twenty-Eight Mansions was established by Chen Zhuo of the Three Kingdoms period, who synthesized ancient constellations and the asterisms created by early astronomers Shi Shen, Gan De and Wuxian. Since the Han and Jin dynasties, stars have been given reference numbers within their asterisms in a system similar to the Bayer or Flamsteed designations, so that individual stars can be identified. For example, Deneb (α Cyg) is referred to as (''Tiān Jīn S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Upsilon Cygni
Upsilon Cygni is a star in the northern constellation of Cygnus. Its name is a Bayer designation that is Latinized from υ Cygni, and abbreviated Upsilon Cyg or υ Cyg. It is visible to the naked eye, having an apparent visual magnitude of 4.43. Based upon an annual parallax shift of , it lies at a distance of roughly 650 light years from the Sun. This is a B-type main sequence star with a stellar classification of B2 Vne. The 'e' suffix indicates this is a Be star, which means it is a rapidly rotating star surrounded by an orbiting gaseous disk. It has a high projected rotational velocity of about 230 km/s, which accounts for the nebulous appearance of its lines as indicated by the 'n' suffix. The emission region of its disk has a radius of . The star itself is being viewed generally "pole-on", as ascertained by the lack of absorption features from the disk. Upsilon Cygni holds 9.3 times the mass of the Sun and is 4.7 times the Sun's radius. The rapid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tau Cygni
Tau Cygni, Latinised from τ Cygni, is a binary star system in the constellation Cygnus, approximately 69 light years away from Earth. This visual binary system has a period of 49.6 years. The main star, 4th magnitude GJ 822.1 A, is a yellowish white subgiant star of the spectral type F2IV. It therefore has a surface temperature of 6,000 to 7,500 kelvins and is larger, hotter, and several times as bright as the Sun. Its companion, 6th magnitude GJ 822.1 B, is a yellow main sequence In astronomy, the main sequence is a classification of stars which appear on plots of stellar color index, color versus absolute magnitude, brightness as a continuous and distinctive band. Stars on this band are known as main-sequence stars or d ... star of the spectral type G0V. It is similar to the Sun in size, surface temperature, and luminosity. Tau Cygni is classified as a δ Scuti variable. The magnitude range is given as 3.65 to 3.75, which is the combined magnitude for both com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nu Cygni
Nu Cygni, Latinized from ν Cygni, is a binary star system in the constellation Cygnus. Its apparent magnitude is 3.94 and it is approximately 374 light years away based on parallax. The brighter component is a magnitude 4.07 A-type giant star with a stellar classification of A0III n, where the 'n' indicates broad "nebulous" absorption lines due to rapid rotation. This white-hued star has an estimated 3.6 times the mass of the Sun and about times the Sun's radius. It is radiating 412 times the Sun's luminosity from its photosphere at an effective temperature of 9,462 K. The magnitude 6.4 companion has an angular separation Angular distance or angular separation is the measure of the angle between the orientation of two straight lines, rays, or vectors in three-dimensional space, or the central angle subtended by the radii through two points on a sphere. When t ... of 0.24 " from the primary. Notes References {{Stars of Cygnus Cygnus (constellatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
30 Cygni
30 Cygni (ο1 Cygni) is a class A5III (white giant) star in the constellation Cygnus. Its apparent magnitude is 4.83 and it is approximately 610 light years away based on parallax. The Bayer letter ο (omicron) has been variously applied to two or three of the stars 30, 31, and 32 Cygni. 30 Cygni has sometimes been designated as ο1 Cygni with the other two stars being ο2 and ο3 respectively. For clarity, it is preferred to use the Flamsteed designation A Flamsteed designation is a combination of a number and constellation name that uniquely identifies most naked eye stars in the 88 modern constellations, modern constellations visible from southern England. They are named after John Flamsteed, au ... 30 Cygni rather than one of the Bayer designations. 30 Cygni is about six arc-minutes from 31 Cygni A and seven arc-minutes from 31 Cygni B. That pair is known as ο1 Cygni, while ο2 Cygni is a degree away. Both ο1 and ο2 are 4th magnitude stars. References {{ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Girl (Chinese Constellation)
The Girl mansion (女宿, pinyin: Nǚ Xiù) is one of the Twenty-eight mansions of the Chinese constellation Traditional Chinese astronomy has a system of dividing the celestial sphere into asterisms or constellations, known as "officials" ( Chinese ''xīng guān''). The Chinese asterisms are generally smaller than the constellations of Hellenisti ...s. It is one of the northern mansions of the Black Tortoise. Asterisms Notes {{Chinese constellation Chinese constellations ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
