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BI Cygni
BI Cygni (BI Cyg, IRC +40408, BD+36 4025) is a red supergiant in the constellation Cygnus. It is an irregular variable star with a maximum brightness of magnitude 8.4 and a minimum of magnitude 9.9. It is considered a member of the Cygnus OB1 stellar association, its distance is around of the Solar System. It is less than a degree south of another variable red supergiant, BC Cygni. BI Cyg is a slow irregular variable star classified as type Lc, an irregular supergiant. Its brightness changes between extremes of magnitude 8.4 and 9.9. Frequency analysis of its light curve shows no significant periods. BI Cyg is one of the largest known stars with a radius around , measured by its angular diameter by the CHARA array. It is about 90,000 times more luminous that the Sun and has a cool effective temperature of . Its mass is estimated at 17solar masses, and it took 12 million years to enter the red supergiant phase. See also *RW Cygni * KY Cygni *NML Cygni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
γ 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 ( Alp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Angular Diameter
The angular diameter, angular size, apparent diameter, or apparent size is an angular separation (in units of angle) describing how large a sphere or circle appears from a given point of view. In the vision sciences, it is called the ''visual angle'', and in optics, it is the ''angular aperture'' (of a lens (optics), lens). The angular diameter can alternatively be thought of as the angular displacement through which an eye or camera must rotate to look from one side of an apparent circle to the opposite side. A person can Angular resolution, resolve with their naked eyes diameters down to about 1 arcminute (approximately 0.017° or 0.0003 radians). This corresponds to 0.3 m at a 1 km distance, or to perceiving Venus as a disk under optimal conditions. Formulation The angular diameter of a circle whose plane is perpendicular to the displacement vector between the point of view and the center of said circle can be calculated using the formula :\delta = 2\arctan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2MASS Objects
Mass is an intrinsic property of a body. It was traditionally believed to be related to the quantity of matter in a body, until the discovery of the atom and particle physics. It was found that different atoms and different elementary particles, theoretically with the same amount of matter, have nonetheless different masses. Mass in modern physics has multiple definitions which are conceptually distinct, but physically equivalent. Mass can be experimentally defined as a measure of the body's inertia, meaning the resistance to acceleration (change of velocity) when a net force is applied. The object's mass also determines the strength of its gravitational attraction to other bodies. The SI base unit of mass is the kilogram (kg). In physics, mass is not the same as weight, even though mass is often determined by measuring the object's weight using a spring scale, rather than balance scale comparing it directly with known masses. An object on the Moon would weigh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Objects With Variable Star Designations
Object may refer to: General meanings * Object (philosophy), a thing, being, or concept ** Object (abstract), an object which does not exist at any particular time or place ** Physical object, an identifiable collection of matter * Goal, an aim, target, or objective * Object (grammar), a sentence element, such as a direct object or an indirect object Science, technology, and mathematics Computing * 3D model, a representation of a physical object * Object (computer science), a language mechanism for binding data with methods that operate on that data ** Object-orientation (other), in which concepts are represented as objects *** Object-oriented programming (OOP), in which an object is an instance of a class or array ** Object (IBM i), the fundamental unit of data storage in the IBM i operating system * Object file, the output of a compiler or other translator program (also known as "object code") * HTML object element Mathematics * Object (mathematics), an abst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slow Irregular Variables
Slow may refer to various basic dictionary-related meanings: * Slow velocity, the rate of change of position of a moving body ** Slow speed, in kinematics, the magnitude of the velocity of an object * Slow tempo, the speed or pace of a piece of music * Slow motion, an effect in film-making * Slow reaction rate, the speed at which a chemical reaction takes place Slow, SLOW, Slowing or Slowness may also refer to: Music * Slow (band), a 1980s Canadian band Albums * ''Slow'' (Richie Kotzen album), 2001 * ''Slow'' (Starflyer 59 album), 2016 * ''Slow'' (Luna Sea album), 2005 * ''Slow'' (Ann Hampton Callaway album), 2004 * ''Slowness'' (album), an album by cantopop singer Kay Tse Songs * "Slow" (Kylie Minogue song), 2003 * "Slow" (Rumer song), 2010 * "Slow" (Matoma song), 2017 * "Slow" (Jackson Wang & Ciara song), 2023 * "Slow" (Black Midi song), 2021 * "Slow", song by The Fratellis from the album ''Eyes Wide, Tongue Tied'' (2015) * "Slow", song by Lisa Mitchell from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
M-type Supergiants
Type M or M type may refer to: Science and technology * Type M, a xD-Picture Card * Type M, a name for the 15 amp AC power plugs and sockets: British and related types#BS 546, BS 546 electrical plug * Vaio Type M, a kind of Vaio computer from Sony * M-type asteroid * m-type filter, an electronic filter * M-type star * M-types, an implementation of inductive type Other uses * Audi Type M, a 1920s car * Beretta 92FS Compact Type M, a pistol * MG M-type, a sports car See also * M class (other) * Class M (other) {{disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Georgia State University
Georgia State University (Georgia State, State, or GSU) is a Public university, public research university in Atlanta, Georgia, United States. Founded in 1913, it is one of the University System of Georgia's four research universities. It is also the second largest institution of higher education by enrollment based in Georgia with a student enrollment of around 50,000, including approximately 33,000 undergraduate and graduate students at the main campus Downtown Atlanta, downtown. Georgia State is Carnegie Classification of Institutions of Higher Education, classified among "List of research universities in the United States#Universities classified as "R1: Doctoral Universities – Very high research spending and doctorate production", R1: Doctoral Universities – Very high research spending and doctorate production". The university is the most comprehensive public institution in Georgia, offering more than 250-degree programs in over 100 fields of study spread across 10 acade ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NML Cygni
NML Cygni or V1489 Cygni (abbreviated to NML Cyg or V1489 Cyg) is a M-type star, red hypergiant or red supergiant (RSG) in the constellation Cygnus (constellation), Cygnus. It is possibly one of the List of largest stars, largest known stars currently known, and is also possibly list of most luminous stars, one of the most luminous and List of most massive stars, massive cool hypergiants, as well as one of the most luminous stars in the Milky Way. The distance of NML Cygni from Earth is estimated to be around 1.6 Parsec#Parsecs and kiloparsecs, kpc, about . It is a part of the Cygnus OB2 association, one of the closest massive associations to the Sun, spanning nearly 2° on the sky or ~ in radius at the distance of . Based on the estimated distance and a measurement of its angular diameter of , NML Cygni's physical radius is estimated to be . If placed at the center of the Solar System, its surface would potentially extend past the orbit of Jupiter. Observational history ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
KY Cygni
KY Cygni is a variable red supergiant of spectral class M3Ia located in the constellation Cygnus. It is approximately 4,700 light-years away. Observations KY Cyg lies near the bright open cluster NGC 6913, but is not thought to be a member. The location is close to the bright star γ Cygni. It was identified as a variable star in 1930, and later named as KY Cygni. The spectrum was given the MK classification of M3 Ia, with only minor adjustments since. KY Cygni is heavily reddened due to interstellar extinction, losing an estimated 7.75 magnitudes at visual wavelengths. It would be a naked eye star if no light was lost. Properties KY Cygni is classified as a luminous red supergiant with a strong stellar wind. It is losing mass at around and has been described as a cool hypergiant. Its properties are uncertain, but the temperature is around 3,500 K. A model fit based on K-band infrared brightness gives a luminosity of , corresponding to a radius of . Another m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RW Cygni
RW Cygni is a semiregular variable star in the constellation Cygnus (constellation), Cygnus, about a degree east of 2nd magnitude γ Cygni. Its apparent magnitude varies between 8.05 and 9.70 and its spectral type between M3 and M4. Distance The Gaia Data Release 2 parallax for RW Cyg is or a distance of around . RW Cygni is assumed to be a member of the Cygnus OB9 stellar association and therefore around 3,600 light-years from the Solar System. Newer observations based on the parallaxes of neighbouring OB stars give RW Cygni a distance of . Properties RW Cygni is a luminous red supergiant with a bolometric luminosity more than . Its spectral type is given in the General Catalogue of Variable Stars as M2-4Ia-Iab, covering the range of previously published values. It has been defined as a standard star for the MK spectral classification of M3-M4Ia-Iab. In 2005, the effective temperature is directly calculated to be 3,600 K, giving a radius of . An alternate cal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar Mass
The solar mass () is a frequently used unit of mass in astronomy, equal to approximately . It is approximately equal to the mass of the Sun. It is often used to indicate the masses of other stars, as well as stellar clusters, nebulae, galaxies and black holes. More precisely, the mass of the Sun is The solar mass is about times the mass of Earth (), or times the mass of Jupiter (). History of measurement The value of the gravitational constant was first derived from measurements that were made by Henry Cavendish in 1798 with a torsion balance. The value he obtained differs by only 1% from the modern value, but was not as precise. The diurnal parallax of the Sun was accurately measured during the transits of Venus in 1761 and 1769, yielding a value of (9 arcseconds, compared to the present value of ). From the value of the diurnal parallax, one can determine the distance to the Sun from the geometry of Earth. The first known estimate of the solar mass was by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CHARA Array
The CHARA (Center for High Angular Resolution Astronomy) array is an optical interferometer, located on Mount Wilson, California. The array consists of six telescopes operating as an astronomical interferometer. Construction was completed in 2003. CHARA is owned by Georgia State University (GSU). Functionality CHARA's six telescopes each have a one-meter diameter mirror to reflect light. They are spread across Mount Wilson to increase the angular resolution of the array. Each of the six telescopes provides a different image, to combine it into one image the light from each telescope is transported through vacuum tubes and fed into a single beam, where they are matched up to within one micron. This process is called interferometry, and allows the array to have the same resolving power as a telescope with a 330-meter mirror, and an angular resolution of 200 micro-arcseconds. History In 1984 CHARA was founded, and with financial support from the National Science Foundation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
